Search Index

Flat list of every learning asset. Use Ctrl+F / Cmd+F to find what you need. Topic aliases are included so synonym searches work.

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Linux

• /proc Filesystem — Topic Pack, L2, 3h
  Topics: /proc Filesystem, Linux Fundamentals, Linux Performance Tuning
  Aliases: procfs, proc, proc-pid, proc-meminfo, proc-cpuinfo, proc-sys, sysctl, virtual-filesystem, linux, linux-basics, filesystem, permissions

• Advanced Bash for Ops — Topic Pack, L1, 5h
  Topics: Bash / Shell Scripting, Linux Fundamentals
  Aliases: bash, shell, scripting, shell-scripting, advanced-bash, linux, linux-basics, filesystem, permissions

• Bash Exercises (Quest Ladder) (CLI) — Exercise Set, L0, 8h
  Topics: Bash / Shell Scripting, Linux Fundamentals
  Aliases: bash, shell, scripting, shell-scripting, advanced-bash, linux, linux-basics, filesystem, permissions

• Bash Flashcards (CLI) — flashcard_deck, L1
  Topics: Bash / Shell Scripting
  Aliases: bash, shell, scripting, shell-scripting, advanced-bash

• Binary Flashcards (CLI) — flashcard_deck, L1
  Topics: Binary & Number Representation
  Aliases: binary, integers, floats, bitwise, encoding, two-s-complement

• Binary and Floats — Topic Pack, L1, 2h
  Topics: Binary & Number Representation
  Aliases: binary, integers, floats, bitwise, encoding, two-s-complement

• Case Study: IPTables Blocking Unexpected — Case Study, L2, 30m
  Topics: Firewalls, Linux Networking Tools
  Aliases: firewall, iptables, nftables, ufw, firewalld, ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute

• Case Study: Inode Exhaustion — Case Study, L1, 30m
  Topics: Linux Fundamentals
  Aliases: linux, linux-basics, filesystem, permissions

• Case Study: Kernel Soft Lockup — Case Study, L2, 30m
  Topics: Linux Fundamentals
  Aliases: linux, linux-basics, filesystem, permissions

• Case Study: OOM Killer Events — Case Study, L2, 30m
  Topics: Linux Fundamentals
  Aliases: linux, linux-basics, filesystem, permissions

• Case Study: Runaway Logs Fill Disk — Case Study, L1, 30m
  Topics: Linux Fundamentals, Filesystems & Storage
  Aliases: linux, linux-basics, filesystem, permissions, ext4, xfs, btrfs, file-systems, df, lsblk, disk-debug, io-troubleshooting

• Case Study: SELinux Denying Service — Case Study, L1, 30m
  Topics: Linux Fundamentals
  Aliases: linux, linux-basics, filesystem, permissions

• Case Study: Stuck NFS Mount — Case Study, L2, 30m
  Topics: Filesystems & Storage, Linux Networking Tools
  Aliases: ext4, xfs, btrfs, file-systems, df, lsblk, disk-debug, io-troubleshooting, smartctl, iostat, fstab, mount-point

• Case Study: Systemd Service Flapping — Case Study, L1, 30m
  Topics: systemd
  Aliases: systemctl, journalctl, services, units

• Case Study: Time Sync Skew Breaks App — Case Study, L2, 30m
  Topics: Linux Fundamentals
  Aliases: linux, linux-basics, filesystem, permissions

• Case Study: Zombie Processes Accumulating — Case Study, L1, 30m
  Topics: Linux Fundamentals
  Aliases: linux, linux-basics, filesystem, permissions

• Cron & Job Scheduling — Topic Pack, L1, 4h
  Topics: Cron & Job Scheduling, Bash / Shell Scripting, systemd
  Aliases: crontab, systemd-timers, cronjob, at, batch, job-scheduling, cron-scheduling, bash, shell, scripting, shell-scripting, advanced-bash

• Cron Flashcards (CLI) — flashcard_deck, L1
  Topics: Cron & Job Scheduling
  Aliases: crontab, systemd-timers, cronjob, at, batch, job-scheduling, cron-scheduling

• DNF Flashcards (CLI) — flashcard_deck, L1
  Topics: DNF Package Manager
  Aliases: dnf5, yum4, dnf-automatic, versionlock, module-streams, reposync

• DNF Package Manager — Topic Pack, L2, 3h
  Topics: DNF Package Manager
  Aliases: dnf5, yum4, dnf-automatic, versionlock, module-streams, reposync

• Debian & Ubuntu Ecosystem — Topic Pack, L1, 6h
  Topics: Debian & Ubuntu Ecosystem, Linux Fundamentals, Package Management
  Aliases: debian, ubuntu, apt, dpkg, ufw, apparmor, netplan, preseed, snap, linux, linux-basics, filesystem

• Debian Ubuntu Flashcards (CLI) — flashcard_deck, L1
  Topics: Debian & Ubuntu Ecosystem
  Aliases: debian, ubuntu, apt, dpkg, ufw, apparmor, netplan, preseed, snap

• Deep Dive: Linux Boot Sequence — deep_dive, L2, 45m
  Topics: Linux Fundamentals, systemd
  Aliases: linux, linux-basics, filesystem, permissions, systemctl, journalctl, services, units

• Deep Dive: Linux Filesystem Internals — deep_dive, L2, 45m
  Topics: Filesystems & Storage, Linux Fundamentals
  Aliases: ext4, xfs, btrfs, file-systems, df, lsblk, disk-debug, io-troubleshooting, smartctl, iostat, fstab, mount-point

• Deep Dive: Linux Memory Management — deep_dive, L2, 45m
  Topics: Linux Fundamentals
  Aliases: linux, linux-basics, filesystem, permissions

• Deep Dive: Linux Network Packet Flow — deep_dive, L2, 45m
  Topics: Linux Networking Tools, Packet Path
  Aliases: ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute, packet-flow, network-path, network-troubleshooting

• Deep Dive: Linux Performance Debugging — deep_dive, L2, 45m
  Topics: Linux Fundamentals, Filesystems & Storage
  Aliases: linux, linux-basics, filesystem, permissions, ext4, xfs, btrfs, file-systems, df, lsblk, disk-debug, io-troubleshooting

• Deep Dive: Linux Process Scheduler — deep_dive, L3, 45m
  Topics: Linux Fundamentals
  Aliases: linux, linux-basics, filesystem, permissions

• Deep Dive: Systemd Architecture — deep_dive, L2, 45m
  Topics: systemd, Linux Fundamentals
  Aliases: systemctl, journalctl, services, units, linux, linux-basics, filesystem, permissions

• Deep Dive: Systemd Service Design Debugging and Hardening — deep_dive, L2, 45m
  Topics: systemd, Linux Hardening
  Aliases: systemctl, journalctl, services, units, os-hardening, cis-benchmark, system-hardening

• Deep Dive: Systemd Timers Journald Cgroups and Resource Control — deep_dive, L2, 45m
  Topics: systemd, Linux Fundamentals
  Aliases: systemctl, journalctl, services, units, linux, linux-basics, filesystem, permissions

• Deep Dive: Systemd Units Dependencies and Ordering — deep_dive, L2, 45m
  Topics: systemd
  Aliases: systemctl, journalctl, services, units

• Deep Dive: eBPF Explained — deep_dive, L3, 45m
  Topics: eBPF, Linux Networking Tools
  Aliases: bpftrace, bcc-tools, kernel-tracing, tcplife, execsnoop, ebpf-observability, ip-command, ss, tcpdump, ethtool, nmcli, mtr

• Disk & Storage Ops — Topic Pack, L1, 5h
  Topics: Disk & Storage Ops, Linux Fundamentals, Filesystems & Storage, RAID, Datacenter RAID & Disk Failures (alias → disk_and_storage_ops)
  Aliases: fdisk, parted, lvm, mdadm, raid, mkfs, fstab, smartctl, iostat, luks, nfs, iscsi

• Environment Variables — Topic Pack, L1, 2h
  Topics: Environment Variables, Linux Fundamentals, Bash / Shell Scripting
  Aliases: env, env-vars, PATH, export, dotenv, profile, bashrc, environment, linux, linux-basics, filesystem, permissions

• Inodes — Topic Pack, L1, 2h
  Topics: Filesystems & Storage
  Aliases: ext4, xfs, btrfs, file-systems, df, lsblk, disk-debug, io-troubleshooting, smartctl, iostat, fstab, mount-point

• Inodes Flashcards (CLI) — flashcard_deck, L1
  Topics: Filesystems & Storage
  Aliases: ext4, xfs, btrfs, file-systems, df, lsblk, disk-debug, io-troubleshooting, smartctl, iostat, fstab, mount-point

• Interview: Linux Server Slow — Scenario, L1, 15m
  Topics: Linux Fundamentals
  Aliases: linux, linux-basics, filesystem, permissions

• Kernel Troubleshooting — Topic Pack, L3, 6h
  Topics: Kernel Troubleshooting, Linux Fundamentals, Filesystems & Storage
  Aliases: dmesg, kernel-panic, crash-dump, kdump, sysrq, oops, linux, linux-basics, filesystem, permissions, ext4, xfs

• LPIC / LFCS Exam Preparation — Topic Pack, L2, 30h
  Topics: LPIC / LFCS Exam, Linux Fundamentals, Bash / Shell Scripting, systemd
  Aliases: lpic, lfcs, lpic-1, lpic-2, linux-foundation, lpi, linux, linux-basics, filesystem, permissions, bash, shell

• LPIC/LFCS Flashcards (CLI) — flashcard_deck, L1
  Topics: LPIC / LFCS Exam
  Aliases: lpic, lfcs, lpic-1, lpic-2, linux-foundation, lpi

• Linux Boot Process — Topic Pack, L1, 3h
  Topics: Linux Boot Process, Linux Fundamentals, systemd
  Aliases: boot, grub, initramfs, uefi, bios, systemd-targets, dracut, kernel-boot, linux, linux-basics, filesystem, permissions

• Linux Data Hoarding — Topic Pack, L2, 4h
  Topics: Linux Data Hoarding
  Aliases: data-hoarding, snapraid, jbod, par2, jdupes, fdupes, rdfind, drive-burn-in, badblocks

• Linux Data Hoarding Flashcards (CLI) — flashcard_deck, L1
  Topics: Linux Data Hoarding
  Aliases: data-hoarding, snapraid, jbod, par2, jdupes, fdupes, rdfind, drive-burn-in, badblocks

• Linux Distribution Comparison — Topic Pack, L1, 4h
  Topics: Linux Distribution Comparison, Debian & Ubuntu Ecosystem, Linux Fundamentals
  Aliases: distro, distros, linux-distributions, rhel-vs-ubuntu, alpine, arch, suse, debian, ubuntu, apt, dpkg, ufw

• Linux Distros Flashcards (CLI) — flashcard_deck, L1
  Topics: Linux Distribution Comparison
  Aliases: distro, distros, linux-distributions, rhel-vs-ubuntu, alpine, arch, suse

• Linux Filesystem Flashcards (CLI) — flashcard_deck, L1
  Topics: Filesystems & Storage
  Aliases: ext4, xfs, btrfs, file-systems, df, lsblk, disk-debug, io-troubleshooting, smartctl, iostat, fstab, mount-point

• Linux Fundamentals Flashcards (CLI) — flashcard_deck, L1
  Topics: Linux Fundamentals
  Aliases: linux, linux-basics, filesystem, permissions

• Linux Kernel Flashcards (CLI) — flashcard_deck, L1
  Topics: Linux Kernel Tuning
  Aliases: sysctl, kernel-tuning, tcp-tuning, ulimit, file-max, somaxconn, io-scheduler, hugepages

• Linux Kernel Tuning — Topic Pack, L2, 4h
  Topics: Linux Kernel Tuning, Linux Performance Tuning
  Aliases: sysctl, kernel-tuning, tcp-tuning, ulimit, file-max, somaxconn, io-scheduler, hugepages, perf, flamegraph, strace, tuning

• Linux Logging — Topic Pack, L1, 4h
  Topics: Linux Logging, Linux Fundamentals, systemd, Logging
  Aliases: syslog, rsyslog, journald, journalctl, logrotate, auditd, dmesg, logger, linux, linux-basics, filesystem, permissions

• Linux Memory Flashcards (CLI) — flashcard_deck, L1
  Topics: Linux Memory Management
  Aliases: memory, oom-killer, swap, vmstat, hugepages, cgroup-memory, overcommit, numa

• Linux Memory Management — Topic Pack, L1, 4h
  Topics: Linux Memory Management, Linux Fundamentals, Linux Performance Tuning
  Aliases: memory, oom-killer, swap, vmstat, hugepages, cgroup-memory, overcommit, numa, linux, linux-basics, filesystem, permissions

• Linux Ops — Topic Pack, L0, 5h
  Topics: Linux Fundamentals, Bash / Shell Scripting, systemd, Package Management, Linux Networking Tools (alias → linux_ops)
  Aliases: linux, linux-basics, filesystem, permissions, bash, shell, scripting, shell-scripting, advanced-bash, systemctl, journalctl, services

• Linux Ops Drills — Drill, L0, 30m
  Topics: Linux Fundamentals, Bash / Shell Scripting
  Aliases: linux, linux-basics, filesystem, permissions, bash, shell, scripting, shell-scripting, advanced-bash

• Linux Ops Storage — Topic Pack, L1, 2h
  Topics: Linux Ops Storage
  Aliases: linux-storage-ops, disk-ops, storage-triage

• Linux Ops Systemd — Topic Pack, L1, 2h
  Topics: Linux Ops systemd
  Aliases: systemd-ops, systemd-triage, service-management

• Linux Performance Flashcards (CLI) — flashcard_deck, L1
  Topics: Linux Performance Tuning
  Aliases: perf, flamegraph, sysctl, strace, tuning, kernel-tuning

• Linux Performance Tuning — Topic Pack, L2, 7h
  Topics: Linux Performance Tuning, Linux Fundamentals, eBPF, Linux Ops Performance Triage
  Aliases: perf, flamegraph, sysctl, strace, tuning, kernel-tuning, linux, linux-basics, filesystem, permissions, bpftrace, bcc-tools

• Linux Processes Flashcards (CLI) — flashcard_deck, L1
  Topics: Process Management
  Aliases: signals, zombie, orphan, nohup, job-control, kill, ps

• Linux Security Flashcards (CLI) — flashcard_deck, L1
  Topics: Linux Hardening
  Aliases: os-hardening, cis-benchmark, system-hardening

• Linux Signals & Process Control — Topic Pack, L1, 3h
  Topics: Linux Signals & Process Control, Linux Fundamentals
  Aliases: signals, sigterm, sigkill, kill, pkill, nohup, disown, job-control, zombie, process-states, linux, linux-basics

• Linux Systemd Flashcards (CLI) — flashcard_deck, L1
  Topics: systemd
  Aliases: systemctl, journalctl, services, units

• Linux Text Processing — Topic Pack, L1, 3h
  Topics: Linux Text Processing, Bash / Shell Scripting
  Aliases: sort, uniq, cut, tr, wc, head, tail, paste, comm, diff, column, text-tools

• Linux Users & Permissions — Topic Pack, L1, 4h
  Topics: Linux Users & Permissions, Linux Fundamentals, Linux Hardening
  Aliases: chmod, chown, acl, sudo, sudoers, users, groups, uid, gid, pam, umask, linux

• Mounts Filesystems — Topic Pack, L1, 2h
  Topics: Mounts & Filesystems (alias)
  Aliases: mount-ops, filesystem-ops, fstab-ops

• Package Management — Topic Pack, L1, 2h
  Topics: Package Management
  Aliases: apt, yum, rpm, dpkg

• Package Management Flashcards (CLI) — flashcard_deck, L1
  Topics: Package Management
  Aliases: apt, yum, rpm, dpkg

• Performance Flashcards (CLI) — flashcard_deck, L1
  Topics: perf Profiling
  Aliases: perf, profiling, performance, tracing

• Pipes & Redirection — Topic Pack, L1, 3h
  Topics: Pipes & Redirection, Bash / Shell Scripting, Linux Fundamentals
  Aliases: pipes, redirection, stdin, stdout, stderr, tee, file-descriptors, process-substitution, bash, shell, scripting, shell-scripting

• Process Management — Topic Pack, L1, 4h
  Topics: Process Management, Linux Fundamentals, Bash / Shell Scripting
  Aliases: signals, zombie, orphan, nohup, job-control, kill, ps, linux, linux-basics, filesystem, permissions, bash

• Runbook: Disk Full — Runbook, L1, 15m
  Topics: Filesystems & Storage
  Aliases: ext4, xfs, btrfs, file-systems, df, lsblk, disk-debug, io-troubleshooting, smartctl, iostat, fstab, mount-point

• Runbook: High CPU (Runaway Process) — Runbook, L1, 15m
  Topics: Linux Performance Tuning, Process Management
  Aliases: perf, flamegraph, sysctl, strace, tuning, kernel-tuning, signals, zombie, orphan, nohup, job-control, kill

• Runbook: OOM Killer Activated — Runbook, L1, 15m
  Topics: Linux Memory Management
  Aliases: memory, oom-killer, swap, vmstat, hugepages, cgroup-memory, overcommit, numa

• Runbook: Systemd Service Crash Loop — Runbook, L1, 15m
  Topics: systemd
  Aliases: systemctl, journalctl, services, units

• Runbook: Zombie Processes Accumulating — Runbook, L2, 15m
  Topics: Process Management, Linux Signals & Process Control
  Aliases: signals, zombie, orphan, nohup, job-control, kill, ps, sigterm, sigkill, pkill, disown, process-states

• SSH Deep Dive — Topic Pack, L1, 4h
  Topics: SSH Deep Dive, Linux Fundamentals, Linux Hardening
  Aliases: ssh, sshd, ssh-keygen, ssh-agent, port-forwarding, bastion, jump-host, scp, sftp, linux, linux-basics, filesystem

• Skillcheck: Bash — Assessment, L0, 30m
  Topics: Bash / Shell Scripting
  Aliases: bash, shell, scripting, shell-scripting, advanced-bash

• Skillcheck: Linux Fundamentals — Assessment, L0, 30m
  Topics: Linux Fundamentals, systemd, Package Management
  Aliases: linux, linux-basics, filesystem, permissions, systemctl, journalctl, services, units, apt, yum, rpm, dpkg

• Strace Flashcards (CLI) — flashcard_deck, L1
  Topics: strace
  Aliases: strace, syscalls, tracing

• Terminal Flashcards (CLI) — flashcard_deck, L1
  Topics: Terminal Internals
  Aliases: terminal, tty, pty, shell, escape_sequences

• Terminal Internals — Topic Pack, L1, 2h
  Topics: Terminal Internals, Bash / Shell Scripting
  Aliases: terminal, tty, pty, shell, escape_sequences, bash, scripting, shell-scripting, advanced-bash

• Tracing Flashcards (CLI) — flashcard_deck, L1
  Topics: Tracing
  Aliases: distributed-tracing-concepts, trace-propagation, span

• Track: Foundations — Reference, L0, 20h
  Topics: Linux Fundamentals, Bash / Shell Scripting, Git, Docker / Containers
  Aliases: linux, linux-basics, filesystem, permissions, bash, shell, scripting, shell-scripting, advanced-bash, version-control, branching, merging

• cgroups & Linux Namespaces — Topic Pack, L2, 4h
  Topics: cgroups & Linux Namespaces, Linux Fundamentals, Container Runtimes
  Aliases: cgroups, namespaces, cgroup-v2, unshare, nsenter, resource-limits, pid-namespace, cgroupfs, linux, linux-basics, filesystem, permissions

• eBPF & Modern Linux Observability — Topic Pack, L3, 5h
  Topics: eBPF, Linux Fundamentals
  Aliases: bpftrace, bcc-tools, kernel-tracing, tcplife, execsnoop, ebpf-observability, linux, linux-basics, filesystem, permissions

• eBPF Flashcards (CLI) — flashcard_deck, L1
  Topics: eBPF
  Aliases: bpftrace, bcc-tools, kernel-tracing, tcplife, execsnoop, ebpf-observability

• iptables & nftables — Topic Pack, L1, 4h
  Topics: iptables & nftables, Linux Fundamentals, Linux Networking Tools
  Aliases: iptables, nftables, firewall, netfilter, conntrack, firewalld, packet-filter, linux, linux-basics, filesystem, permissions, ip-command

• mergerfs — Topic Pack, L2, 3h
  Topics: mergerfs
  Aliases: merger-fs, fuse-union, trapexit, union-filesystem, jbod-pooling

• perf Profiling — Topic Pack, L2, 2h
  Topics: perf Profiling, Tracing
  Aliases: perf, profiling, performance, tracing, distributed-tracing-concepts, trace-propagation, span

• rsync — Topic Pack, L1, 3h
  Topics: rsync, Linux Fundamentals
  Aliases: rsync, file-sync, delta-transfer, backup, remote-copy, rclone, linux, linux-basics, filesystem, permissions

• strace — Topic Pack, L1, 2h
  Topics: strace, Tracing
  Aliases: strace, syscalls, tracing, distributed-tracing-concepts, trace-propagation, span

• systemctl & journalctl Deep Dive — Topic Pack, L1, 4h
  Topics: systemctl & journalctl Deep Dive, systemd, Linux Fundamentals
  Aliases: systemctl, journalctl, unit-files, timer-units, socket-activation, systemd-analyze, drop-in, services, units, linux, linux-basics, filesystem

• tar & Compression — Topic Pack, L1, 2h
  Topics: tar & Compression, Linux Fundamentals
  Aliases: tar, gzip, bzip2, xz, zstd, compression, archive, pigz, zip, linux, linux-basics, filesystem

• tmux & screen — Topic Pack, L1, 2h
  Topics: tmux & screen, Linux Fundamentals
  Aliases: tmux, screen, terminal-multiplexer, detach, session, pane, window, linux, linux-basics, filesystem, permissions

Networking

• ARP — Topic Pack, L1, 2h
  Topics: ARP
  Aliases: arp-table, mac-address, neighbor-discovery

• ARP Flashcards (CLI) — flashcard_deck, L1
  Topics: ARP
  Aliases: arp-table, mac-address, neighbor-discovery

• BGP EVPN / VXLAN — Topic Pack, L2, 5h
  Topics: BGP EVPN / VXLAN
  Aliases: evpn, vxlan, vtep, vni, spine-leaf, overlay-networking, dc-fabric, mp-bgp

• Case Study: ARP Flux Duplicate IP — Case Study, L2, 30m
  Topics: ARP, Linux Networking Tools
  Aliases: arp-table, mac-address, neighbor-discovery, ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute

• Case Study: Asymmetric Routing One Direction — Case Study, L2, 30m
  Topics: Routing
  Aliases: routes, gateway, bgp, ospf, static-routes, asymmetric-routing

• Case Study: BGP Peer Flapping — Case Study, L2, 30m
  Topics: Routing
  Aliases: routes, gateway, bgp, ospf, static-routes, asymmetric-routing

• Case Study: DHCP Relay Broken — Case Study, L1, 30m
  Topics: Linux Networking Tools, VLANs
  Aliases: ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute, vlan, trunk, 802.1q, tagged, untagged

• Case Study: DNS Resolution Slow — Case Study, L1, 30m
  Topics: DNS
  Aliases: domain-name-system, coredns, dig, nslookup, resolve, dns-ops

• Case Study: DNS Split Horizon Confusion — Case Study, L2, 30m
  Topics: DNS
  Aliases: domain-name-system, coredns, dig, nslookup, resolve, dns-ops

• Case Study: Duplex Mismatch Symptoms — Case Study, L1, 30m
  Topics: TCP/IP, Linux Networking Tools
  Aliases: tcp, ip, networking-fundamentals, osi-model, layers, networking, ip-command, ss, tcpdump, ethtool, nmcli, mtr

• Case Study: Firewall Shadow Rule — Case Study, L2, 30m
  Topics: Firewalls
  Aliases: firewall, iptables, nftables, ufw, firewalld

• Case Study: Jumbo Frames Partial — Case Study, L2, 30m
  Topics: MTU, Linux Networking Tools
  Aliases: mtu-blackhole, jumbo-frames, path-mtu, fragmentation, ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute

• Case Study: LACP Mismatch One Link Hot — Case Study, L2, 30m
  Topics: LACP / Link Aggregation
  Aliases: link-aggregation, bonding, etherchannel, port-channel

• Case Study: MTU Blackhole TLS Stalls — Case Study, L2, 30m
  Topics: MTU
  Aliases: mtu-blackhole, jumbo-frames, path-mtu, fragmentation

• Case Study: Multicast Not Crossing Router — Case Study, L2, 30m
  Topics: Routing, VLANs
  Aliases: routes, gateway, bgp, ospf, static-routes, asymmetric-routing, vlan, trunk, 802.1q, tagged, untagged

• Case Study: NAT Exhaustion Intermittent — Case Study, L2, 30m
  Topics: TCP/IP
  Aliases: tcp, ip, networking-fundamentals, osi-model, layers, networking

• Case Study: Network Loop Broadcast Storm — Case Study, L2, 30m
  Topics: VLANs
  Aliases: vlan, trunk, 802.1q, tagged, untagged

• Case Study: OSPF Stuck In Exstart — Case Study, L2, 30m
  Topics: Routing
  Aliases: routes, gateway, bgp, ospf, static-routes, asymmetric-routing

• Case Study: Proxy ARP Causing Issues — Case Study, L2, 30m
  Topics: ARP, Routing
  Aliases: arp-table, mac-address, neighbor-discovery, routes, gateway, bgp, ospf, static-routes, asymmetric-routing

• Case Study: SSL Cert Chain Incomplete — Case Study, L1, 30m
  Topics: TLS & PKI
  Aliases: pki, certificates, x509, ca-chain, cert-rotation, ssl, cert-manager, tls

• Case Study: Source Routing Policy Miss — Case Study, L2, 30m
  Topics: Routing, Linux Networking Tools
  Aliases: routes, gateway, bgp, ospf, static-routes, asymmetric-routing, ip-command, ss, tcpdump, ethtool, nmcli, mtr

• Case Study: TCP RST After Idle — Case Study, L2, 30m
  Topics: TCP/IP
  Aliases: tcp, ip, networking-fundamentals, osi-model, layers, networking

• Case Study: VLAN Trunk Mistag — Case Study, L1, 30m
  Topics: VLANs
  Aliases: vlan, trunk, 802.1q, tagged, untagged

• Cisco Flashcards (CLI) — flashcard_deck, L1
  Topics: Cisco CLI
  Aliases: ios, show-commands, cisco-basics, cisco-fundamentals-for-devops

• Cisco Fundamentals for DevOps — Topic Pack, L1, 4h
  Topics: Cisco CLI, VLANs, STP / Spanning Tree, LACP / Link Aggregation
  Aliases: ios, show-commands, cisco-basics, cisco-fundamentals-for-devops, vlan, trunk, 802.1q, tagged, untagged, spanning-tree, rstp, bridge-loops

• DHCP & IP Address Management — Topic Pack, L1, 4h
  Topics: DHCP & IP Address Management, TCP/IP, DNS
  Aliases: dhcp, ipam, dhcp-relay, lease, ip-allocation, tcp, ip, networking-fundamentals, osi-model, layers, networking, domain-name-system

• DHCP Flashcards (CLI) — flashcard_deck, L1
  Topics: DHCP & IP Address Management
  Aliases: dhcp, ipam, dhcp-relay, lease, ip-allocation

• DNS Deep Dive — Topic Pack, L1, 4h
  Topics: DNS Deep Dive, DNS
  Aliases: dns-internals, dig, zone-files, dns-resolution, coredns-debug, route53, split-horizon, domain-name-system, coredns, nslookup, resolve, dns-ops

• DNS Flashcards (CLI) — flashcard_deck, L1
  Topics: DNS
  Aliases: domain-name-system, coredns, dig, nslookup, resolve, dns-ops

• DNS Operations — Topic Pack, L2, 4h
  Topics: DNS
  Aliases: domain-name-system, coredns, dig, nslookup, resolve, dns-ops

• DNSSEC & DNS Security — Topic Pack, L2, 4h
  Topics: DNSSEC & DNS Security
  Aliases: dnssec, dns-security, doh, dot, dns-over-https, dns-over-tls, zone-signing, ksk, zsk

• Deep Dive: AWS VPC Internals — deep_dive, L2, 45m
  Topics: Routing, Linux Networking Tools
  Aliases: routes, gateway, bgp, ospf, static-routes, asymmetric-routing, ip-command, ss, tcpdump, ethtool, nmcli, mtr

• Deep Dive: TCP/IP Deep Dive — deep_dive, L2, 45m
  Topics: TCP/IP, Linux Networking Tools
  Aliases: tcp, ip, networking-fundamentals, osi-model, layers, networking, ip-command, ss, tcpdump, ethtool, nmcli, mtr

• Deep Dive: TLS Handshake — deep_dive, L2, 45m
  Topics: TLS & PKI, TCP/IP
  Aliases: pki, certificates, x509, ca-chain, cert-rotation, ssl, cert-manager, tls, tcp, ip, networking-fundamentals, osi-model

• Dnssec Flashcards (CLI) — flashcard_deck, L1
  Topics: DNSSEC & DNS Security
  Aliases: dnssec, dns-security, doh, dot, dns-over-https, dns-over-tls, zone-signing, ksk, zsk

• Email Infrastructure — Topic Pack, L1, 3h
  Topics: Email Infrastructure
  Aliases: spf, dkim, dmarc, smtp, email, mx-records, dmarc-reports, arc, email-deliverability

• Firewalls — Topic Pack, L1, 2h
  Topics: Firewalls
  Aliases: firewall, iptables, nftables, ufw, firewalld

• Firewalls Flashcards (CLI) — flashcard_deck, L1
  Topics: Firewalls
  Aliases: firewall, iptables, nftables, ufw, firewalld

• HAProxy & Nginx for Ops — Topic Pack, L2, 4h
  Topics: Load Balancing
  Aliases: load-balancer, haproxy, nginx-lb, reverse-proxy

• HTTP Protocol — Topic Pack, L0, 3h
  Topics: HTTP Protocol, TLS & PKI
  Aliases: http, https, web, apis, rest, pki, certificates, x509, ca-chain, cert-rotation, ssl, cert-manager

• LACP — Topic Pack, L1, 2h
  Topics: LACP / Link Aggregation
  Aliases: link-aggregation, bonding, etherchannel, port-channel

• LACP Flashcards (CLI) — flashcard_deck, L1
  Topics: LACP / Link Aggregation
  Aliases: link-aggregation, bonding, etherchannel, port-channel

• Linux Networking Flashcards (CLI) — flashcard_deck, L1
  Topics: Linux Networking Tools
  Aliases: ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute

• Load Balancing Flashcards (CLI) — flashcard_deck, L1
  Topics: Load Balancing
  Aliases: load-balancer, haproxy, nginx-lb, reverse-proxy

• MTU — Topic Pack, L1, 2h
  Topics: MTU
  Aliases: mtu-blackhole, jumbo-frames, path-mtu, fragmentation

• MTU Flashcards (CLI) — flashcard_deck, L1
  Topics: MTU
  Aliases: mtu-blackhole, jumbo-frames, path-mtu, fragmentation

• Mellanox Switches — Topic Pack, L2, 4h
  Topics: Mellanox Switches
  Aliases: mellanox, nvidia-networking, onyx, mlnx-os, spectrum, wjh, ufm, roce

• Mellanox Switches Flashcards (CLI) — flashcard_deck, L1
  Topics: Mellanox Switches
  Aliases: mellanox, nvidia-networking, onyx, mlnx-os, spectrum, wjh, ufm, roce

• NAT — Topic Pack, L1, 2h
  Topics: NAT
  Aliases: snat, dnat, masquerade, port-forwarding

• NAT Flashcards (CLI) — flashcard_deck, L1
  Topics: NAT
  Aliases: snat, dnat, masquerade, port-forwarding

• Network Automation — Topic Pack, L2, 5h
  Topics: Network Automation
  Aliases: napalm, nornir, netmiko, network-automation, pyats, genie, netconf, restconf, gnmi, openconfig

• Networking Deep Dive — Topic Pack, L1, 6h
  Topics: TCP/IP, DNS, VLANs, Routing, LACP / Link Aggregation, MTU, Linux Networking Tools, Cisco CLI, TLS & PKI
  Aliases: tcp, ip, networking-fundamentals, osi-model, layers, networking, domain-name-system, coredns, dig, nslookup, resolve, dns-ops

• Networking Drills — Drill, L1, 30m
  Topics: TCP/IP, DNS, Linux Networking Tools
  Aliases: tcp, ip, networking-fundamentals, osi-model, layers, networking, domain-name-system, coredns, dig, nslookup, resolve, dns-ops

• Networking Flashcards (CLI) — flashcard_deck, L1
  Topics: TCP/IP
  Aliases: tcp, ip, networking-fundamentals, osi-model, layers, networking

• Networking Troubleshooting — Topic Pack, L1, 5h
  Topics: Networking Troubleshooting, Networking Troubleshooting Tools, Linux Networking Tools, TCP/IP
  Aliases: network-debug, connectivity-issues, packet-loss, latency, tcpdump, nmap, netcat, iperf3, mtr, traceroute, arping, dig

• Packet Path Flashcards (CLI) — flashcard_deck, L1
  Topics: Packet Path
  Aliases: packet-flow, network-path, network-troubleshooting

• Routing — Topic Pack, L1, 2h
  Topics: Routing
  Aliases: routes, gateway, bgp, ospf, static-routes, asymmetric-routing

• Routing Flashcards (CLI) — flashcard_deck, L1
  Topics: Routing
  Aliases: routes, gateway, bgp, ospf, static-routes, asymmetric-routing

• Runbook: DNS Resolution Failure — Runbook, L1, 15m
  Topics: DNS, Kubernetes Networking, Networking Troubleshooting
  Aliases: domain-name-system, coredns, dig, nslookup, resolve, dns-ops, cni, network-policies, ingress, service-mesh, network-debug, connectivity-issues

• Runbook: Load Balancer Health Check Failure — Runbook, L2, 15m
  Topics: Load Balancing, Networking Troubleshooting
  Aliases: load-balancer, haproxy, nginx-lb, reverse-proxy, network-debug, connectivity-issues, packet-loss, latency

• Runbook: MTU Mismatch — Runbook, L2, 15m
  Topics: MTU, Networking Troubleshooting
  Aliases: mtu-blackhole, jumbo-frames, path-mtu, fragmentation, network-debug, connectivity-issues, packet-loss, latency

• Runbook: Network Partition (Split Brain / Partial Connectivity) — Runbook, L2, 20m
  Topics: Networking Troubleshooting
  Aliases: network-debug, connectivity-issues, packet-loss, latency

• Runbook: TLS Certificate Expiry — Runbook, L2, 15m
  Topics: TLS & PKI
  Aliases: pki, certificates, x509, ca-chain, cert-rotation, ssl, cert-manager, tls

• STP (Spanning Tree) — Topic Pack, L1, 2h
  Topics: STP / Spanning Tree
  Aliases: spanning-tree, rstp, bridge-loops

• STP Flashcards (CLI) — flashcard_deck, L1
  Topics: STP / Spanning Tree
  Aliases: spanning-tree, rstp, bridge-loops

• Scenario: Asymmetric Routing — Scenario, L2, 20m
  Topics: Routing, Linux Networking Tools
  Aliases: routes, gateway, bgp, ospf, static-routes, asymmetric-routing, ip-command, ss, tcpdump, ethtool, nmcli, mtr

• Scenario: DNS Looks Fine but App Fails — Scenario, L2, 20m
  Topics: DNS, TLS & PKI
  Aliases: domain-name-system, coredns, dig, nslookup, resolve, dns-ops, pki, certificates, x509, ca-chain, cert-rotation, ssl

• Scenario: Duplex Mismatch — Scenario, L1, 20m
  Topics: Linux Networking Tools
  Aliases: ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute

• Scenario: MTU Blackhole — Scenario, L2, 20m
  Topics: MTU, Linux Networking Tools
  Aliases: mtu-blackhole, jumbo-frames, path-mtu, fragmentation, ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute

• Scenario: VLAN Trunk Mismatch — Scenario, L2, 20m
  Topics: VLANs, Cisco CLI
  Aliases: vlan, trunk, 802.1q, tagged, untagged, ios, show-commands, cisco-basics, cisco-fundamentals-for-devops

• Skillcheck: Networking Fundamentals — Assessment, L1, 30m
  Topics: TCP/IP, DNS, VLANs, Routing
  Aliases: tcp, ip, networking-fundamentals, osi-model, layers, networking, domain-name-system, coredns, dig, nslookup, resolve, dns-ops

• Subnetting & IP Addressing — Topic Pack, L1, 2h
  Topics: Subnetting & IP Addressing
  Aliases: subnetting, cidr, ip-addressing, subnet-mask, vlsm

• TCP/IP Deep Dive — Topic Pack, L2, 5h
  Topics: TCP/IP Deep Dive, TCP/IP
  Aliases: tcp-states, tcp-handshake, congestion-control, bbr, time-wait, window-size, mss, nagle, tcp, ip, networking-fundamentals, osi-model

• TLS Flashcards (CLI) — flashcard_deck, L1
  Topics: TLS & PKI
  Aliases: pki, certificates, x509, ca-chain, cert-rotation, ssl, cert-manager, tls

• Tailscale & Zero Trust Networking — Topic Pack, L2, 3h
  Topics: Tailscale & Zero Trust Networking, VPN & Tunneling
  Aliases: tailscale, wireguard, zero-trust, mesh-vpn, tailnet, headscale, ztna, openvpn, ipsec, ssh-tunnel, overlay-network, vpn-tunneling

• Tcpdump Flashcards (CLI) — flashcard_deck, L1
  Topics: Networking Troubleshooting Tools
  Aliases: tcpdump, nmap, netcat, iperf3, mtr, traceroute, arping, dig, ss, network-debug

• VLANs — Topic Pack, L1, 2h
  Topics: VLANs
  Aliases: vlan, trunk, 802.1q, tagged, untagged

• VPN & Tunneling — Topic Pack, L2, 5h
  Topics: VPN & Tunneling, Firewalls, Linux Networking Tools
  Aliases: openvpn, ipsec, ssh-tunnel, overlay-network, vpn-tunneling, firewall, iptables, nftables, ufw, firewalld, ip-command, ss

• VPN Flashcards (CLI) — flashcard_deck, L1
  Topics: VPN & Tunneling
  Aliases: openvpn, ipsec, ssh-tunnel, overlay-network, vpn-tunneling

• Vlans Flashcards (CLI) — flashcard_deck, L1
  Topics: VLANs
  Aliases: vlan, trunk, 802.1q, tagged, untagged

• Wireshark & Packet Analysis — Topic Pack, L2, 4h
  Topics: Wireshark & Packet Analysis, Linux Networking Tools
  Aliases: wireshark, packet-capture, tshark, pcap, packet-analysis, protocol-analysis, ip-command, ss, tcpdump, ethtool, nmcli, mtr

• gRPC & Protocol Buffers — Topic Pack, L2, 3h
  Topics: gRPC & Protocol Buffers, HTTP Protocol
  Aliases: grpc, protobuf, protocol-buffers, grpc-streaming, grpc-web, grpc-gateway, http, https, web, apis, rest

Datacenter & Hardware

• Bare-Metal Provisioning — Topic Pack, L2, 5h
  Topics: PXE / Provisioning, Out-of-Band Management, Server Hardware
  Aliases: pxe-boot, imaging, golden-image, kickstart, preseed, idrac, ilo, ipmi, bmc, serial-console, oob, oob-provisioning

• Case Study: BIOS Settings Reset After CMOS — Case Study, L1, 30m
  Topics: Firmware / BIOS / UEFI, Server Hardware
  Aliases: bios, uefi, firmware-update, post, dimm, cpu, nic, hba, lshw, dmidecode, dmesg

• Case Study: BMC Clock Skew Cert Failure — Case Study, L2, 30m
  Topics: BMC (Baseboard Management Controller), Out-of-Band Management, TLS & PKI
  Aliases: baseboard-management-controller, bmc-firmware, bmc-network, bmc-reset, idrac, ilo, ipmi, bmc, serial-console, oob, oob-provisioning, datacenter-provisioning

• Case Study: Bonding Failover Not Working — Case Study, L1, 30m
  Topics: LACP / Link Aggregation
  Aliases: link-aggregation, bonding, etherchannel, port-channel

• Case Study: Cable Management Wrong Port — Case Study, L1, 30m
  Topics: Rack & Stack, Server Hardware
  Aliases: racking, cabling, labeling, airflow, power, pdu, dimm, cpu, nic, hba, lshw, dmidecode

• Case Study: Disk Full Root Services Down — Case Study, L1, 30m
  Topics: Filesystems & Storage, Linux Fundamentals
  Aliases: ext4, xfs, btrfs, file-systems, df, lsblk, disk-debug, io-troubleshooting, smartctl, iostat, fstab, mount-point

• Case Study: Firmware Update Boot Loop — Case Study, L2, 30m
  Topics: Firmware / BIOS / UEFI, Server Hardware
  Aliases: bios, uefi, firmware-update, post, dimm, cpu, nic, hba, lshw, dmidecode, dmesg

• Case Study: HBA Firmware Mismatch — Case Study, L2, 30m
  Topics: Firmware / BIOS / UEFI, Storage (SAN/NAS/DAS)
  Aliases: bios, uefi, firmware-update, post, san, nas, das, iscsi, nfs-storage, portworx, minio, storage-arrays

• Case Study: Link Flaps Bad Optic — Case Study, L1, 30m
  Topics: Server Hardware, Rack & Stack
  Aliases: dimm, cpu, nic, hba, lshw, dmidecode, dmesg, racking, cabling, labeling, airflow, power

• Case Study: Memory ECC Errors Increasing — Case Study, L1, 30m
  Topics: Server Hardware
  Aliases: dimm, cpu, nic, hba, lshw, dmidecode, dmesg

• Case Study: NVMe Drive Disappeared — Case Study, L2, 30m
  Topics: Storage (SAN/NAS/DAS), Filesystems & Storage
  Aliases: san, nas, das, iscsi, nfs-storage, portworx, minio, storage-arrays, ext4, xfs, btrfs, file-systems

• Case Study: OS Install Fails RAID Controller — Case Study, L2, 30m
  Topics: RAID, Firmware / BIOS / UEFI
  Aliases: raid-levels, raid-rebuild, disk-arrays, megaraid, smart, bios, uefi, firmware-update, post

• Case Study: PXE Boot Fails UEFI Mismatch — Case Study, L1, 30m
  Topics: PXE / Provisioning, Firmware / BIOS / UEFI
  Aliases: pxe-boot, imaging, golden-image, kickstart, preseed, bios, uefi, firmware-update, post

• Case Study: Power Supply Redundancy Lost — Case Study, L1, 30m
  Topics: Power & UPS, Server Hardware
  Aliases: ups, pdu, power-redundancy, power-management, dimm, cpu, nic, hba, lshw, dmidecode, dmesg

• Case Study: RAID Degraded Rebuild Latency — Case Study, L2, 30m
  Topics: RAID
  Aliases: raid-levels, raid-rebuild, disk-arrays, megaraid, smart

• Case Study: Rack PDU Overload Alert — Case Study, L1, 30m
  Topics: Power & UPS, Rack & Stack
  Aliases: ups, pdu, power-redundancy, power-management, racking, cabling, labeling, airflow, power

• Case Study: Serial Console Garbled — Case Study, L1, 30m
  Topics: Out-of-Band Management, Server Hardware
  Aliases: idrac, ilo, ipmi, bmc, serial-console, oob, oob-provisioning, datacenter-provisioning, remote-provisioning, bare-metal-provisioning, dimm, cpu

• Case Study: Server Intermittent Reboot — Case Study, L2, 30m
  Topics: Server Hardware, Power & UPS
  Aliases: dimm, cpu, nic, hba, lshw, dmidecode, dmesg, ups, pdu, power-redundancy, power-management

• Case Study: Server Remote Console Lag — Case Study, L1, 30m
  Topics: Out-of-Band Management, Server Hardware
  Aliases: idrac, ilo, ipmi, bmc, serial-console, oob, oob-provisioning, datacenter-provisioning, remote-provisioning, bare-metal-provisioning, dimm, cpu

• Case Study: Thermal Throttle Fan Failure — Case Study, L1, 30m
  Topics: Server Hardware
  Aliases: dimm, cpu, nic, hba, lshw, dmidecode, dmesg

• Case Study: iDRAC Unreachable OS Up — Case Study, L1, 30m
  Topics: Out-of-Band Management, BMC (Baseboard Management Controller)
  Aliases: idrac, ilo, ipmi, bmc, serial-console, oob, oob-provisioning, datacenter-provisioning, remote-provisioning, bare-metal-provisioning, baseboard-management-controller, bmc-firmware

• Datacenter & Server Hardware — Topic Pack, L1, 6h
  Topics: Rack & Stack, Out-of-Band Management, RAID, Firmware / BIOS / UEFI, PXE / Provisioning, Server Hardware
  Aliases: racking, cabling, labeling, airflow, power, pdu, idrac, ilo, ipmi, bmc, serial-console, oob

• Datacenter Drills — Drill, L1, 30m
  Topics: Rack & Stack, Out-of-Band Management
  Aliases: racking, cabling, labeling, airflow, power, pdu, idrac, ilo, ipmi, bmc, serial-console, oob

• Datacenter Flashcards (CLI) — flashcard_deck, L1
  Topics: Out-of-Band Management
  Aliases: idrac, ilo, ipmi, bmc, serial-console, oob, oob-provisioning, datacenter-provisioning, remote-provisioning, bare-metal-provisioning

• Deep Dive: Dell Linux PowerEdge — deep_dive, L2, 45m
  Topics: Server Hardware, Out-of-Band Management
  Aliases: dimm, cpu, nic, hba, lshw, dmidecode, dmesg, idrac, ilo, ipmi, bmc, serial-console

• Deep Dive: RAID and Storage Internals — deep_dive, L2, 45m
  Topics: RAID, Storage (SAN/NAS/DAS)
  Aliases: raid-levels, raid-rebuild, disk-arrays, megaraid, smart, san, nas, das, iscsi, nfs-storage, portworx, minio

• Dell PowerEdge Servers — Topic Pack, L1, 2h
  Topics: Server Hardware, Out-of-Band Management, RAID, Firmware / BIOS / UEFI
  Aliases: dimm, cpu, nic, hba, lshw, dmidecode, dmesg, idrac, ilo, ipmi, bmc, serial-console

• Firmware — Topic Pack, L1, 2h
  Topics: Firmware / BIOS / UEFI
  Aliases: bios, uefi, firmware-update, post

• Firmware Flashcards (CLI) — flashcard_deck, L1
  Topics: Firmware / BIOS / UEFI
  Aliases: bios, uefi, firmware-update, post

• IPMI and ipmitool — Topic Pack, L1, 3h
  Topics: IPMI / ipmitool, BMC (Baseboard Management Controller), Out-of-Band Management, Server Hardware, Hardware Security
  Aliases: ipmitool, ipmi-protocol, rmcp, lanplus, udp-623, baseboard-management-controller, bmc-firmware, bmc-network, bmc-reset, idrac, ilo, ipmi

• Interview: Server Won't POST — Scenario, L2, 15m
  Topics: Firmware / BIOS / UEFI, Server Hardware
  Aliases: bios, uefi, firmware-update, post, dimm, cpu, nic, hba, lshw, dmidecode, dmesg

• Packer — Topic Pack, L1, 2h
  Topics: Packer
  Aliases: hashicorp-packer, image-builder, machine-images, ami-builder

• Power — Topic Pack, L1, 2h
  Topics: Power & UPS
  Aliases: ups, pdu, power-redundancy, power-management

• Redfish API — Topic Pack, L1, 2h
  Topics: Redfish API, BMC (Baseboard Management Controller), Out-of-Band Management, Server Hardware, Hardware Security, Firmware / BIOS / UEFI
  Aliases: redfish-api, dmtf-redfish, rest-bmc, redfish-v1, server-management-api, baseboard-management-controller, bmc-firmware, bmc-network, bmc-reset, idrac, ilo, ipmi

• Scenario: NIC Flapping / LACP Mismatch — Scenario, L2, 20m
  Topics: LACP / Link Aggregation, Server Hardware, Linux Networking Tools
  Aliases: link-aggregation, bonding, etherchannel, port-channel, dimm, cpu, nic, hba, lshw, dmidecode, dmesg, ip-command

• Scenario: OOB Unreachable but Host Responds — Scenario, L2, 20m
  Topics: Out-of-Band Management, Linux Networking Tools
  Aliases: idrac, ilo, ipmi, bmc, serial-console, oob, oob-provisioning, datacenter-provisioning, remote-provisioning, bare-metal-provisioning, ip-command, ss

• Scenario: RAID Array Degraded — Scenario, L1, 20m
  Topics: RAID, Server Hardware
  Aliases: raid-levels, raid-rebuild, disk-arrays, megaraid, smart, dimm, cpu, nic, hba, lshw, dmidecode, dmesg

• Scenario: Server Won't Boot After Update — Scenario, L1, 20m
  Topics: Firmware / BIOS / UEFI, Out-of-Band Management
  Aliases: bios, uefi, firmware-update, post, idrac, ilo, ipmi, bmc, serial-console, oob, oob-provisioning, datacenter-provisioning

• Scenario: Thermal Throttling — Scenario, L1, 20m
  Topics: Server Hardware, Rack & Stack
  Aliases: dimm, cpu, nic, hba, lshw, dmidecode, dmesg, racking, cabling, labeling, airflow, power

• Server Hardware — Topic Pack, L1, 2h
  Topics: Server Hardware
  Aliases: dimm, cpu, nic, hba, lshw, dmidecode, dmesg

• Server Hardware Flashcards (CLI) — flashcard_deck, L1
  Topics: Server Hardware
  Aliases: dimm, cpu, nic, hba, lshw, dmidecode, dmesg

• Skillcheck: Datacenter — Assessment, L1, 30m
  Topics: Rack & Stack, Out-of-Band Management, RAID, Server Hardware
  Aliases: racking, cabling, labeling, airflow, power, pdu, idrac, ilo, ipmi, bmc, serial-console, oob

• Storage Flashcards (CLI) — flashcard_deck, L1
  Topics: Storage (SAN/NAS/DAS)
  Aliases: san, nas, das, iscsi, nfs-storage, portworx, minio, storage-arrays

• Storage Operations — Topic Pack, L2, 5h
  Topics: Storage (SAN/NAS/DAS), Filesystems & Storage, RAID
  Aliases: san, nas, das, iscsi, nfs-storage, portworx, minio, storage-arrays, ext4, xfs, btrfs, file-systems

• VMware — Topic Pack, L2, 4h
  Topics: VMware, Virtualization
  Aliases: vsphere, esxi, vcenter, vmware-ha, vmware-drs, vmotion, vmdk, vsan, kvm, qemu, libvirt, hypervisor

• VMware Flashcards (CLI) — flashcard_deck, L1
  Topics: VMware
  Aliases: vsphere, esxi, vcenter, vmware-ha, vmware-drs, vmotion, vmdk, vsan

• Virtualization — Topic Pack, L2, 5h
  Topics: Virtualization, Server Hardware, Linux Fundamentals
  Aliases: kvm, qemu, libvirt, hypervisor, virt-manager, dimm, cpu, nic, hba, lshw, dmidecode, dmesg

• Virtualization Flashcards (CLI) — flashcard_deck, L1
  Topics: Virtualization
  Aliases: kvm, qemu, libvirt, hypervisor, virt-manager

Kubernetes

• API Gateways & Ingress — Topic Pack, L2, 5h
  Topics: API Gateways & Ingress, Kubernetes Networking, Load Balancing
  Aliases: kong, traefik, api-management, rate-limiting, ingress-advanced, api-gateways, cni, network-policies, ingress, coredns, service-mesh, load-balancer

• Api Gateway Flashcards (CLI) — flashcard_deck, L1
  Topics: API Gateways & Ingress
  Aliases: kong, traefik, api-management, rate-limiting, ingress-advanced, api-gateways

• Argo Workflows — Topic Pack, L2, 4h
  Topics: Argo Workflows
  Aliases: argo-workflows, dag-workflows, workflow-engine, argo-events, cronworkflow

• Case Study: CNI Broken After Restart — Case Study, L2, 30m
  Topics: Kubernetes Networking
  Aliases: cni, network-policies, ingress, coredns, service-mesh

• Case Study: CoreDNS Timeout Pod DNS — Case Study, L2, 30m
  Topics: Kubernetes Networking, DNS
  Aliases: cni, network-policies, ingress, coredns, service-mesh, domain-name-system, dig, nslookup, resolve, dns-ops

• Case Study: CrashLoopBackOff No Logs — Case Study, L1, 30m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Case Study: DaemonSet Blocks Eviction — Case Study, L2, 30m
  Topics: Kubernetes Core, Node Lifecycle & Maintenance
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, node-upgrade, node-drain, pdb, kubelet, cordon, drain

• Case Study: Drain Blocked by PDB — Case Study, L2, 30m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Case Study: ImagePullBackOff Registry Auth — Case Study, L1, 30m
  Topics: Kubernetes Core, Docker / Containers
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, containers, dockerfile, docker-compose, images

• Case Study: Node Pressure Evictions — Case Study, L2, 30m
  Topics: Kubernetes Core, OOMKilled
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, oom, out-of-memory, resource-limits, memory

• Case Study: Persistent Volume Stuck Terminating — Case Study, L2, 30m
  Topics: Kubernetes Storage, Kubernetes Core
  Aliases: pv, pvc, storage-class, csi, kubernetes, pods, deployments, services, k8s, openshift

• Case Study: Resource Quota Blocking Deploy — Case Study, L2, 30m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Case Study: Service No Endpoints — Case Study, L1, 30m
  Topics: Kubernetes Networking, Kubernetes Core
  Aliases: cni, network-policies, ingress, coredns, service-mesh, kubernetes, pods, deployments, services, k8s, openshift

• Chaos Engineering Scripts (CLI) — Exercise Set, L2, 2h
  Topics: Incident Response, Kubernetes Core
  Aliases: incidents, triage, forensics, rca, postmortem, chaos-engineering, kubernetes, pods, deployments, services, k8s, openshift

• Cilium & eBPF Networking — Topic Pack, L2, 4h
  Topics: Cilium & eBPF Networking, eBPF, Kubernetes Networking
  Aliases: cilium, hubble, cilium-cni, ebpf-networking, cluster-mesh, network-observability, bpftrace, bcc-tools, kernel-tracing, tcplife, execsnoop, ebpf-observability

• Cilium Flashcards (CLI) — flashcard_deck, L1
  Topics: Cilium & eBPF Networking
  Aliases: cilium, hubble, cilium-cni, ebpf-networking, cluster-mesh, network-observability

• Consul Flashcards (CLI) — flashcard_deck, L1
  Topics: HashiCorp Consul
  Aliases: consul, consul-connect, service-discovery, hashicorp-consul

• Container Base Images Flashcards (CLI) — flashcard_deck, L1
  Topics: Container Base Images
  Aliases: base-image, distroless, scratch, alpine-container, ubi, chainguard, wolfi

• Container Images — Topic Pack, L1, 3h
  Topics: Container Base Images, Docker / Containers, Container Image Optimization (alias → container_images), Container Image Scanning (alias → container_images)
  Aliases: base-image, distroless, scratch, alpine-container, ubi, chainguard, wolfi, containers, dockerfile, docker-compose, images, multi-stage

• Container Runtime Drills — Drill, L2, 30m
  Topics: Container Runtimes
  Aliases: containerd, cri-o, runc, cgroups, namespaces, container-runtime-debug

• Container Runtime Flashcards (CLI) — flashcard_deck, L1
  Topics: Container Runtimes
  Aliases: containerd, cri-o, runc, cgroups, namespaces, container-runtime-debug

• CrashLoopBackOff — Topic Pack, L1, 2h
  Topics: CrashLoopBackOff (alias)
  Aliases: crash-loop-backoff, pod-crashloop

• Crashloopbackoff Flashcards (CLI) — flashcard_deck, L1
  Topics: CrashLoopBackOff (alias)
  Aliases: crash-loop-backoff, pod-crashloop

• Database Operations Flashcards (CLI) — flashcard_deck, L1
  Topics: Database Operations
  Aliases: statefulsets, database, mysql, backup-restore

• Database Operations on Kubernetes — Topic Pack, L2, 4h
  Topics: Database Operations, Kubernetes Storage
  Aliases: statefulsets, database, mysql, backup-restore, pv, pvc, storage-class, csi

• Database Ops Drills — Drill, L2, 30m
  Topics: Database Operations
  Aliases: statefulsets, database, mysql, backup-restore

• Deep Dive: Kubernetes Networking — deep_dive, L2, 45m
  Topics: Kubernetes Networking, Linux Networking Tools
  Aliases: cni, network-policies, ingress, coredns, service-mesh, ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute

• Deep Dive: Kubernetes Pod Lifecycle — deep_dive, L2, 45m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Deep Dive: Kubernetes Scheduler — deep_dive, L3, 45m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Docker — Topic Pack, L1, 2h
  Topics: Docker / Containers
  Aliases: containers, dockerfile, docker-compose, images

• Docker Drills — Drill, L1, 30m
  Topics: Docker / Containers
  Aliases: containers, dockerfile, docker-compose, images

• Docker Exercises (Quest Ladder) (CLI) — Exercise Set, L0, 8h
  Topics: Docker / Containers
  Aliases: containers, dockerfile, docker-compose, images

• Envoy Flashcards (CLI) — flashcard_deck, L1
  Topics: Envoy Proxy
  Aliases: envoy-proxy, envoy-xds, l7-proxy

• Envoy Proxy — Topic Pack, L2, 4h
  Topics: Envoy Proxy
  Aliases: envoy-proxy, envoy-xds, l7-proxy

• HashiCorp Consul — Topic Pack, L2, 4h
  Topics: HashiCorp Consul
  Aliases: consul, consul-connect, service-discovery, hashicorp-consul

• Helm — Topic Pack, L1, 2h
  Topics: Helm
  Aliases: helm-charts, helm-upgrade, helm-rollback, values-files

• Incident Simulator (18 scenarios) (CLI) — Exercise Set, L2, 4h
  Topics: Incident Response, CrashLoopBackOff, Probes (Liveness/Readiness), OOMKilled, DNS, HPA / Autoscaling, Helm, Prometheus, Loki
  Aliases: incidents, triage, forensics, rca, postmortem, chaos-engineering, crashloop, crash-loop, pod-restart, liveness, readiness, startup-probe

• Interview: Database Failover During Deploy — Scenario, L3, 15m
  Topics: Database Operations
  Aliases: statefulsets, database, mysql, backup-restore

• Interview: Deployment Stuck Progressing — Scenario, L2, 15m
  Topics: Kubernetes Core, Probes (Liveness/Readiness)
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, liveness, readiness, startup-probe, healthcheck

• Interview: Docker Container Debugging — Scenario, L1, 15m
  Topics: Docker / Containers, Container Runtimes
  Aliases: containers, dockerfile, docker-compose, images, containerd, cri-o, runc, cgroups, namespaces, container-runtime-debug

• Interview: HPA Not Scaling — Scenario, L2, 15m
  Topics: HPA / Autoscaling
  Aliases: horizontal-pod-autoscaler, autoscaling, metrics-server

• Interview: Ingress 404 — Scenario, L2, 15m
  Topics: Kubernetes Networking
  Aliases: cni, network-policies, ingress, coredns, service-mesh

• Interview: Kyverno Blocking Deploys — Scenario, L2, 15m
  Topics: Policy Engines
  Aliases: opa, gatekeeper, kyverno, admission-control

• Interview: Pods OOMKilled — Scenario, L2, 15m
  Topics: OOMKilled
  Aliases: oom, out-of-memory, resource-limits, memory

• Interview: RBAC Forbidden — Scenario, L2, 15m
  Topics: RBAC
  Aliases: roles, clusterroles, service-accounts, rbac

• Interview: Service Mesh 503s — Scenario, L3, 15m
  Topics: Service Mesh
  Aliases: istio, linkerd, envoy, sidecar, mtls

• Interview: etcd Space Exceeded — Scenario, L3, 15m
  Topics: etcd
  Aliases: etcd-backup, etcd-restore, etcd-cluster

• Investigation Engine (CLI) — Exercise Set, L2, 2h
  Topics: Incident Response
  Aliases: incidents, triage, forensics, rca, postmortem, chaos-engineering

• Istio Flashcards (CLI) — flashcard_deck, L1
  Topics: Istio Service Mesh
  Aliases: istio-mesh, istiod, istio-pilot

• Istio Service Mesh — Topic Pack, L2, 5h
  Topics: Istio Service Mesh
  Aliases: istio-mesh, istiod, istio-pilot

• K8s Ecosystem — Topic Pack, L0, 6h
  Topics: K8s Ecosystem, Kubernetes Operators
  Aliases: kubernetes-ecosystem, k8s-landscape, cncf, operators, crds, custom-resources, operator-sdk

• K8s Networking — Topic Pack, L1, 2h
  Topics: Kubernetes Networking
  Aliases: cni, network-policies, ingress, coredns, service-mesh

• K8s RBAC — Topic Pack, L1, 2h
  Topics: RBAC
  Aliases: roles, clusterroles, service-accounts, rbac

• K8s Storage — Topic Pack, L1, 2h
  Topics: Kubernetes Storage
  Aliases: pv, pvc, storage-class, csi

• Kubernetes Advanced Operations Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Debugging
  Aliases: k8s-debug, pod-troubleshooting, kubectl-debug

• Kubernetes Concept Chain — Topic Pack, L0, 2h
  Topics: Kubernetes Concept Chain, Kubernetes Core
  Aliases: concept-chain, k8s-concepts, k8s-architecture, why-kubernetes, kubernetes, pods, deployments, services, k8s, openshift

• Kubernetes Concept Chain Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Concept Chain
  Aliases: concept-chain, k8s-concepts, k8s-architecture, why-kubernetes

• Kubernetes Config Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Kubernetes Core Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Kubernetes Debugging Playbook — Topic Pack, L2, 4h
  Topics: Kubernetes Debugging, Kubernetes Core
  Aliases: k8s-debug, pod-troubleshooting, kubectl-debug, kubernetes, pods, deployments, services, k8s, openshift

• Kubernetes Exercises (Quest Ladder) (CLI) — Exercise Set, L1, 10h
  Topics: Kubernetes Core, Kubernetes Networking, Kubernetes Storage, RBAC, Probes (Liveness/Readiness), HPA / Autoscaling
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, cni, network-policies, ingress, coredns, service-mesh, pv

• Kubernetes General Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Kubernetes Networking Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Networking
  Aliases: cni, network-policies, ingress, coredns, service-mesh

• Kubernetes Node Lifecycle — Topic Pack, L2, 4h
  Topics: Node Lifecycle & Maintenance
  Aliases: node-upgrade, node-drain, pdb, kubelet, cordon, drain, uncordon, node-maintenance, daemonsets

• Kubernetes Node Lifecycle Flashcards (CLI) — flashcard_deck, L1
  Topics: Node Lifecycle & Maintenance
  Aliases: node-upgrade, node-drain, pdb, kubelet, cordon, drain, uncordon, node-maintenance, daemonsets

• Kubernetes Operations Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Kubernetes Operators Drills — Drill, L3, 30m
  Topics: K8s Ecosystem
  Aliases: kubernetes-ecosystem, k8s-landscape, cncf

• Kubernetes Operators Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Operators
  Aliases: operators, crds, custom-resources, operator-sdk

• Kubernetes Ops (Production) — Topic Pack, L2, 5h
  Topics: Node Lifecycle & Maintenance, Probes (Liveness/Readiness), CrashLoopBackOff, OOMKilled, HPA / Autoscaling, Kubernetes Networking, K8s HPA (alias → k8s_ops), K8s Probes (alias → k8s_ops)
  Aliases: node-upgrade, node-drain, pdb, kubelet, cordon, drain, uncordon, node-maintenance, daemonsets, liveness, readiness, startup-probe

• Kubernetes Pods & Scheduling — Topic Pack, L1, 4h
  Topics: Kubernetes Pods & Scheduling, Kubernetes Core
  Aliases: pods, scheduling, affinity, taints, tolerations, resource-limits, qos, pdb, priority, kubernetes, deployments, services

• Kubernetes RBAC Flashcards (CLI) — flashcard_deck, L1
  Topics: RBAC
  Aliases: roles, clusterroles, service-accounts, rbac

• Kubernetes Security Flashcards (CLI) — flashcard_deck, L1
  Topics: RBAC
  Aliases: roles, clusterroles, service-accounts, rbac

• Kubernetes Services & Ingress — Topic Pack, L1, 4h
  Topics: Kubernetes Services & Ingress, Kubernetes Networking
  Aliases: services, ingress, clusterip, nodeport, loadbalancer, gateway-api, network-policy, coredns, cni, network-policies, service-mesh

• Kubernetes Services Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Services & Ingress
  Aliases: services, ingress, clusterip, nodeport, loadbalancer, gateway-api, network-policy, coredns

• Kubernetes Storage Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Storage
  Aliases: pv, pvc, storage-class, csi

• Kubernetes Troubleshooting Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Debugging
  Aliases: k8s-debug, pod-troubleshooting, kubectl-debug

• Kubernetes Workloads Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Pods & Scheduling
  Aliases: pods, scheduling, affinity, taints, tolerations, resource-limits, qos, pdb, priority

• Kustomize — Topic Pack, L1, 3h
  Topics: Kustomize, Kubernetes Core
  Aliases: kustomize, kustomization, overlays, patches, kubectl-kustomize, kubernetes, pods, deployments, services, k8s, openshift

• Lab: HPA Live Scaling (CLI) — Lab, L1, 30m
  Topics: HPA / Autoscaling, Kubernetes Core
  Aliases: horizontal-pod-autoscaler, autoscaling, metrics-server, kubernetes, pods, deployments, services, k8s, openshift

• Lab: Readiness Probe Failure (CLI) — Lab, L1, 30m
  Topics: Probes (Liveness/Readiness), Kubernetes Core
  Aliases: liveness, readiness, startup-probe, healthcheck, kubernetes, pods, deployments, services, k8s, openshift

• Lab: Resource Limits OOMKilled (CLI) — Lab, L1, 30m
  Topics: OOMKilled, Kubernetes Core
  Aliases: oom, out-of-memory, resource-limits, memory, kubernetes, pods, deployments, services, k8s, openshift

• Multi Tenancy Flashcards (CLI) — flashcard_deck, L1
  Topics: Multi-Tenancy Patterns
  Aliases: tenant-isolation, noisy-neighbor, fair-scheduling, namespace-isolation

• Multi-Tenancy Patterns — Topic Pack, L2, 5h
  Topics: Multi-Tenancy Patterns, RBAC, Kubernetes Networking, Policy Engines
  Aliases: tenant-isolation, noisy-neighbor, fair-scheduling, namespace-isolation, roles, clusterroles, service-accounts, rbac, cni, network-policies, ingress, coredns

• Node Maintenance — Topic Pack, L1, 2h
  Topics: Node Lifecycle & Maintenance
  Aliases: node-upgrade, node-drain, pdb, kubelet, cordon, drain, uncordon, node-maintenance, daemonsets

• OOMKilled — Topic Pack, L1, 2h
  Topics: OOMKilled (alias)
  Aliases: oom-killed, out-of-memory-killed

• Oomkilled Flashcards (CLI) — flashcard_deck, L1
  Topics: OOMKilled (alias)
  Aliases: oom-killed, out-of-memory-killed

• Openshift Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Policy Engine Drills — Drill, L2, 30m
  Topics: Policy Engines
  Aliases: opa, gatekeeper, kyverno, admission-control

• Policy Engines (OPA / Kyverno) — Topic Pack, L2, 4h
  Topics: Policy Engines, RBAC
  Aliases: opa, gatekeeper, kyverno, admission-control, roles, clusterroles, service-accounts, rbac

• Policy Engines Flashcards (CLI) — flashcard_deck, L1
  Topics: Policy Engines
  Aliases: opa, gatekeeper, kyverno, admission-control

• Progressive Delivery — Topic Pack, L2, 4h
  Topics: Progressive Delivery
  Aliases: canary, blue-green, argo-rollouts, flagger, traffic-splitting, canary-deployment

• Runbook: Deployment Stuck / Rollout Stalled — Runbook, L1, 15m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Runbook: Disaster Recovery — Runbook, L2, 20m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Runbook: HPA Not Scaling — Runbook, L2, 15m
  Topics: HPA / Autoscaling
  Aliases: horizontal-pod-autoscaler, autoscaling, metrics-server

• Runbook: HPA Thrashing (Rapid Scale Up/Down) — Runbook, L2, 15m
  Topics: HPA / Autoscaling, Kubernetes Core
  Aliases: horizontal-pod-autoscaler, autoscaling, metrics-server, kubernetes, pods, deployments, services, k8s, openshift

• Runbook: ImagePullBackOff — Runbook, L1, 15m
  Topics: Docker / Containers, Kubernetes Core
  Aliases: containers, dockerfile, docker-compose, images, kubernetes, pods, deployments, services, k8s, openshift

• Runbook: Ingress 404 — Runbook, L1, 15m
  Topics: Kubernetes Networking
  Aliases: cni, network-policies, ingress, coredns, service-mesh

• Runbook: Ingress 502 Bad Gateway — Runbook, L2, 15m
  Topics: Kubernetes Networking, Kubernetes Services & Ingress
  Aliases: cni, network-policies, ingress, coredns, service-mesh, services, clusterip, nodeport, loadbalancer, gateway-api, network-policy

• Runbook: Istio 503 Errors — Runbook, L3, 15m
  Topics: Service Mesh
  Aliases: istio, linkerd, envoy, sidecar, mtls

• Runbook: Kyverno Blocking Workloads — Runbook, L2, 15m
  Topics: Policy Engines
  Aliases: opa, gatekeeper, kyverno, admission-control

• Runbook: NetworkPolicy Block — Runbook, L2, 15m
  Topics: Kubernetes Networking
  Aliases: cni, network-policies, ingress, coredns, service-mesh

• Runbook: Node NotReady — Runbook, L1, 15m
  Topics: Node Lifecycle & Maintenance
  Aliases: node-upgrade, node-drain, pdb, kubelet, cordon, drain, uncordon, node-maintenance, daemonsets

• Runbook: OOMKilled Container — Runbook, L1, 15m
  Topics: Kubernetes Core, OOMKilled
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, oom, out-of-memory, resource-limits, memory

• Runbook: PVC Stuck in Pending — Runbook, L1, 15m
  Topics: Kubernetes Storage
  Aliases: pv, pvc, storage-class, csi

• Runbook: Pod CrashLoopBackOff — Runbook, L1, 15m
  Topics: CrashLoopBackOff, Kubernetes Core
  Aliases: crashloop, crash-loop, pod-restart, kubernetes, pods, deployments, services, k8s, openshift

• Runbook: Pod Eviction — Runbook, L2, 15m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Runbook: RBAC Forbidden — Runbook, L2, 15m
  Topics: RBAC
  Aliases: roles, clusterroles, service-accounts, rbac

• Runbook: Readiness Probe Failed — Runbook, L1, 15m
  Topics: Probes (Liveness/Readiness), Kubernetes Core
  Aliases: liveness, readiness, startup-probe, healthcheck, kubernetes, pods, deployments, services, k8s, openshift

• Runbook: Velero Backup & Restore — Runbook, L2, 15m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Runbook: etcd Backup & Restore — Runbook, L2, 20m
  Topics: etcd
  Aliases: etcd-backup, etcd-restore, etcd-cluster

• Runbook: etcd High Latency / Slow Operations — Runbook, L3, 20m
  Topics: etcd
  Aliases: etcd-backup, etcd-restore, etcd-cluster

• Scenario: etcd Troubleshooting — Scenario, L3, 30m
  Topics: etcd
  Aliases: etcd-backup, etcd-restore, etcd-cluster

• Service Mesh — Topic Pack, L3, 5h
  Topics: Service Mesh, Kubernetes Networking
  Aliases: istio, linkerd, envoy, sidecar, mtls, cni, network-policies, ingress, coredns, service-mesh

• Service Mesh Drills — Drill, L3, 30m
  Topics: Service Mesh
  Aliases: istio, linkerd, envoy, sidecar, mtls

• Service Mesh Flashcards (CLI) — flashcard_deck, L1
  Topics: Service Mesh
  Aliases: istio, linkerd, envoy, sidecar, mtls

• Skillcheck: Container Runtime Debug — Assessment, L2, 30m
  Topics: Container Runtimes
  Aliases: containerd, cri-o, runc, cgroups, namespaces, container-runtime-debug

• Skillcheck: Database Ops — Assessment, L2, 30m
  Topics: Database Operations
  Aliases: statefulsets, database, mysql, backup-restore

• Skillcheck: Docker — Assessment, L0, 30m
  Topics: Docker / Containers
  Aliases: containers, dockerfile, docker-compose, images

• Skillcheck: Kubernetes — Assessment, L1, 45m
  Topics: Kubernetes Core, Probes (Liveness/Readiness), HPA / Autoscaling
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, liveness, readiness, startup-probe, healthcheck, horizontal-pod-autoscaler, autoscaling

• Skillcheck: Kubernetes Operators — Assessment, L3, 30m
  Topics: K8s Ecosystem
  Aliases: kubernetes-ecosystem, k8s-landscape, cncf

• Skillcheck: Kubernetes Under the Covers — Assessment, L2, 45m
  Topics: Kubernetes Core, Kubernetes Networking, Node Lifecycle & Maintenance
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, cni, network-policies, ingress, coredns, service-mesh, node-upgrade

• Skillcheck: Policy Engines — Assessment, L2, 30m
  Topics: Policy Engines
  Aliases: opa, gatekeeper, kyverno, admission-control

• Skillcheck: Service Mesh — Assessment, L3, 30m
  Topics: Service Mesh
  Aliases: istio, linkerd, envoy, sidecar, mtls

• Skillcheck: etcd — Assessment, L2, 30m
  Topics: etcd
  Aliases: etcd-backup, etcd-restore, etcd-cluster

• Track: Containers — Reference, L0, 10h
  Topics: Docker / Containers
  Aliases: containers, dockerfile, docker-compose, images

• Track: Kubernetes Core — Reference, L1, 15h
  Topics: Kubernetes Core, Probes (Liveness/Readiness), Kubernetes Networking, Kubernetes Storage, RBAC
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, liveness, readiness, startup-probe, healthcheck, cni, network-policies

• cert-manager — Topic Pack, L1, 3h
  Topics: cert-manager
  Aliases: cert-manager, lets-encrypt, acme, tls-automation, certificate-lifecycle, clusterissuer

• etcd — Topic Pack, L1, 2h
  Topics: etcd
  Aliases: etcd-backup, etcd-restore, etcd-cluster

• etcd Drills — Drill, L2, 30m
  Topics: etcd
  Aliases: etcd-backup, etcd-restore, etcd-cluster

• etcd Flashcards (CLI) — flashcard_deck, L1
  Topics: etcd
  Aliases: etcd-backup, etcd-restore, etcd-cluster

• kubectl Debugging Cheatsheet — Reference, L1, 15m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• kubectl Drills — Drill, L1, 45m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

DevOps & Tooling

• AI Tools for DevOps — Topic Pack, L1, 4h
  Topics: AI Tools for DevOps
  Aliases: ai, llm, chatgpt, claude, copilot, codex, prompt-engineering, ai-tools, generativeai

• AI-Assisted DevOps Cookbook — Reference, L1, 2h
  Topics: AI Tools for DevOps
  Aliases: ai, llm, chatgpt, claude, copilot, codex, prompt-engineering, ai-tools, generativeai

• Adversarial Interview Gauntlet (30 sequences) — Scenario, L2, 15h
  Topics: Kubernetes Core, Prometheus, CI/CD, TCP/IP, Linux Fundamentals
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack

• Ansible Automation — Topic Pack, L1, 5h
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Ansible Core Flashcards (CLI) — flashcard_deck, L1
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Ansible Deep Dive — Topic Pack, L2, 5h
  Topics: Ansible Deep Dive, Ansible
  Aliases: ansible-roles, ansible-vault, ansible-collections, jinja2, dynamic-inventory, molecule, playbooks, roles, inventory, ansible-galaxy, chef, puppet

• Ansible Drills — Drill, L1, 30m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Ansible Exercises (Quest Ladder) (CLI) — Exercise Set, L1, 8h
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Ansible Lab: Conditionals and Loops — Lab, L1, 25m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Ansible Lab: Facts and Variables — Lab, L0, 20m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Ansible Lab: Install Nginx (Idempotency) — Lab, L1, 20m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Ansible Lab: Ping and Debug — Lab, L0, 15m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Ansible Lab: Roles — Lab, L1, 20m
  Topics: Ansible, Ansible Deep Dive
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management, ansible-roles, ansible-vault, ansible-collections, jinja2

• Ansible Lab: Templates and Handlers — Lab, L1, 25m
  Topics: Ansible, Ansible Deep Dive
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management, ansible-roles, ansible-vault, ansible-collections, jinja2

• Ansible Lab: Vault (Secrets Management) — Lab, L2, 25m
  Topics: Ansible, Ansible Deep Dive
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management, ansible-roles, ansible-vault, ansible-collections, jinja2

• Ansible Operations Flashcards (CLI) — flashcard_deck, L1
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Ansible Playbooks Flashcards (CLI) — flashcard_deck, L1
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Argo Flashcards (CLI) — flashcard_deck, L1
  Topics: GitOps
  Aliases: argocd, argo, flux, desired-state, drift-detection

• ArgoCD & GitOps — Topic Pack, L2, 5h
  Topics: ArgoCD & GitOps
  Aliases: argocd, gitops, fluxcd, flux, pull-based-delivery, app-of-apps, applicationset

• Automation — Topic Pack, L1, 1h
  Topics: Configuration Management
  Aliases: configuration-management, config-management, config-drift, infrastructure-as-code

• Backstage & Developer Portals — Topic Pack, L2, 3h
  Topics: Backstage & Developer Portals, Platform Engineering
  Aliases: backstage, spotify-backstage, developer-portal, software-catalog, techdocs, scaffolder, internal-developer-platform, idp, golden-path, self-service, developer-experience

• Break/Fix: Handler Name Mismatch — Scenario, L1, 10m
  Topics: Ansible, Ansible Deep Dive
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management, ansible-roles, ansible-vault, ansible-collections, jinja2

• Break/Fix: Jinja2 Syntax Error in Template — Scenario, L1, 15m
  Topics: Ansible, Ansible Deep Dive
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management, ansible-roles, ansible-vault, ansible-collections, jinja2

• Break/Fix: Privilege Escalation Missing — Scenario, L1, 10m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Break/Fix: Task Ordering / Dependency — Scenario, L1, 15m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Break/Fix: Undefined Variable + Bare Jinja2 — Scenario, L1, 15m
  Topics: Ansible, Ansible Deep Dive
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management, ansible-roles, ansible-vault, ansible-collections, jinja2

• Break/Fix: Wrong Host Scope — Scenario, L1, 10m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Break/Fix: Wrong Module Parameter — Scenario, L0, 10m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Break/Fix: YAML Indentation Error — Scenario, L0, 10m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• CI Pipeline Documentation — Reference, L1, 15m
  Topics: CI/CD
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

• CI/CD Drills — Drill, L1, 30m
  Topics: CI/CD
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

• CI/CD Flashcards (CLI) — flashcard_deck, L1
  Topics: CI/CD
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

• CI/CD Pipelines & Patterns — Topic Pack, L1, 8h
  Topics: CI/CD, CI/CD Pipelines Realities, CI/CD Patterns
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul, pipeline-realities, cicd-real-world, pipeline-gotchas, ci-cd-patterns, deployment-strategies, canary

• CSS Flashcards (CLI) — flashcard_deck, L1
  Topics: CSS
  Aliases: css, frontend, web, stylesheets

• CSS Fundamentals — Topic Pack, L0, 2h
  Topics: CSS
  Aliases: css, frontend, web, stylesheets

• Capacity Planning — Topic Pack, L2, 4h
  Topics: Capacity Planning, SRE Practices, Prometheus
  Aliases: forecasting, resource-modeling, growth-planning, trend-analysis, site-reliability, toil, error-budget, reliability-engineering, capacity-planning, sre-practices, metrics, promql

• Capacity Planning Flashcards (CLI) — flashcard_deck, L1
  Topics: Capacity Planning
  Aliases: forecasting, resource-modeling, growth-planning, trend-analysis

• Career Engineering for Ops People — Topic Pack, L0, 4h
  Topics: Career Engineering
  Aliases: resume, interview-prep, career-strategy, job-search, impact-stories, career-engineering

• Case Study: API Latency Spike — BGP Route Leak, Fix Is Network ACL — Case Study, L2, 30m
  Topics: BGP EVPN / VXLAN, Linux Networking Tools
  Aliases: evpn, vxlan, vtep, vni, spine-leaf, overlay-networking, dc-fabric, mp-bgp, ip-command, ss, tcpdump, ethtool

• Case Study: Alert Storm — Flapping Health Checks — Case Study, L2, 30m
  Topics: Alerting Rules, Kubernetes Core
  Aliases: alertmanager, alert-rules, pagerduty, on-call, alerting-rules, kubernetes, pods, deployments, services, k8s, openshift

• Case Study: Ansible Playbook Hangs — SSH Agent Forwarding Blocked by Firewall — Case Study, L2, 30m
  Topics: Ansible, iptables & nftables
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management, iptables, nftables, firewall, netfilter

• Case Study: Backup Job Failing — iSCSI Target Unreachable, VLAN Misconfigured — Case Study, L2, 30m
  Topics: Storage (SAN/NAS/DAS), VLANs
  Aliases: san, nas, das, iscsi, nfs-storage, portworx, minio, storage-arrays, vlan, trunk, 802.1q, tagged

• Case Study: CI Pipeline Fails — Docker Layer Cache Corruption — Case Study, L2, 30m
  Topics: Docker / Containers, Linux Fundamentals
  Aliases: containers, dockerfile, docker-compose, images, linux, linux-basics, filesystem, permissions

• Case Study: Canary Deploy Routing to Wrong Backend — Ingress Misconfigured — Case Study, L2, 30m
  Topics: Kubernetes Networking, Kubernetes Core
  Aliases: cni, network-policies, ingress, coredns, service-mesh, kubernetes, pods, deployments, services, k8s, openshift

• Case Study: Container Vuln Scanner False Positive Blocks Deploy — Case Study, L2, 30m
  Topics: Docker / Containers, Linux Fundamentals
  Aliases: containers, dockerfile, docker-compose, images, linux, linux-basics, filesystem, permissions

• Case Study: DNS Looks Broken — TLS Expired, Fix Is Cert-Manager — Case Study, L2, 30m
  Topics: DNS, TLS & PKI, Kubernetes Core
  Aliases: domain-name-system, coredns, dig, nslookup, resolve, dns-ops, pki, certificates, x509, ca-chain, cert-rotation, ssl

• Case Study: Database Replication Lag — Root Cause Is RAID Degradation — Case Study, L2, 30m
  Topics: RAID, Server Hardware
  Aliases: raid-levels, raid-rebuild, disk-arrays, megaraid, smart, dimm, cpu, nic, hba, lshw, dmidecode, dmesg

• Case Study: Deployment Stuck — ImagePull Auth Failure, Vault Secret Rotation — Case Study, L2, 30m
  Topics: Kubernetes Core, TLS & PKI
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, pki, certificates, x509, ca-chain, cert-rotation, ssl

• Case Study: Disk Full — Runaway Logs, Fix Is Loki Retention — Case Study, L2, 30m
  Topics: Linux Fundamentals, Prometheus
  Aliases: linux, linux-basics, filesystem, permissions, metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog

• Case Study: Grafana Dashboard Empty — Prometheus Blocked by NetworkPolicy — Case Study, L2, 30m
  Topics: Prometheus, Kubernetes Networking
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog, cni, network-policies, ingress, coredns, service-mesh

• Case Study: HPA Flapping — Metrics Server Clock Skew, Fix Is NTP — Case Study, L2, 30m
  Topics: Kubernetes Core, Linux Fundamentals
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, linux, linux-basics, filesystem, permissions

• Case Study: Job Queue Backlog — Worker Pod CPU Throttled by cgroup — Case Study, L2, 30m
  Topics: Kubernetes Core, Linux Fundamentals
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, linux, linux-basics, filesystem, permissions

• Case Study: Node NotReady — NIC Firmware Bug, Fix Is Ansible Playbook — Case Study, L2, 30m
  Topics: Kubernetes Core, Firmware / BIOS / UEFI, Ansible
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, bios, uefi, firmware-update, post, playbooks, roles

• Case Study: Pod OOMKilled — Memory Leak in Sidecar, Fix Is Helm Values — Case Study, L2, 30m
  Topics: Kubernetes Core, OOMKilled, Helm
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, oom, out-of-memory, resource-limits, memory, helm-charts, helm-upgrade

• Case Study: SSH Timeout — MTU Mismatch, Fix Is Terraform Variable — Case Study, L2, 30m
  Topics: MTU, Terraform
  Aliases: mtu-blackhole, jumbo-frames, path-mtu, fragmentation, iac, infrastructure-as-code, hcl, tfstate

• Case Study: Service Mesh 503s — Envoy Misconfigured, RBAC Policy — Case Study, L2, 30m
  Topics: Kubernetes Networking, Linux Networking Tools
  Aliases: cni, network-policies, ingress, coredns, service-mesh, ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute

• Case Study: Terraform Apply Fails — State Lock Stuck, DynamoDB Throttle — Case Study, L2, 30m
  Topics: Terraform, Linux Fundamentals
  Aliases: iac, infrastructure-as-code, hcl, tfstate, linux, linux-basics, filesystem, permissions

• Case Study: User Auth Failing — OIDC Cert Expired, Cloud KMS Rotation — Case Study, L2, 30m
  Topics: TLS & PKI, Kubernetes Core
  Aliases: pki, certificates, x509, ca-chain, cert-rotation, ssl, cert-manager, tls, kubernetes, pods, deployments, services

• Ceph Storage — Topic Pack, L2, 5h
  Topics: Ceph Storage
  Aliases: ceph, cephadm, rook-ceph, rados, rbd, cephfs, rgw, crush-map, osd, ceph-storage

• Certificates — Topic Pack, L2, 1h
  Topics: Certificates
  Aliases: tls-certificates, ssl-certificates, pki, certificate-lifecycle

• Change Management — Topic Pack, L1, 4h
  Topics: Change Management, SRE Practices, Incident Response
  Aliases: change-window, rollback-plan, cab, change-freeze, change-control, site-reliability, toil, error-budget, reliability-engineering, capacity-planning, sre-practices, incidents

• Change Management Flashcards (CLI) — flashcard_deck, L1
  Topics: Change Management
  Aliases: change-window, rollback-plan, cab, change-freeze, change-control

• Chaos Engineering & Fault Injection — Topic Pack, L2, 5h
  Topics: Chaos Engineering, Kubernetes Core
  Aliases: chaos-mesh, litmus, fault-injection, game-day, resilience-testing, kubernetes, pods, deployments, services, k8s, openshift

• Chaos Engineering Flashcards (CLI) — flashcard_deck, L1
  Topics: Chaos Engineering
  Aliases: chaos-mesh, litmus, fault-injection, game-day, resilience-testing

• Chef Flashcards (CLI) — flashcard_deck, L1
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Circleci Flashcards (CLI) — flashcard_deck, L1
  Topics: CI/CD
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

• Claude Code — Topic Pack, L1, 2h
  Topics: Claude Code
  Aliases: claude, claude-ai, ai-coding-assistant, claude-cli

• Claude Code Flashcards (CLI) — flashcard_deck, L1
  Topics: Claude Code
  Aliases: claude, claude-ai, ai-coding-assistant, claude-cli

• Cloud Ops Basics — Topic Pack, L1, 4h

• Compliance Flashcards (CLI) — flashcard_deck, L1
  Topics: Compliance & Audit
  Aliases: openscap, inspec, stig, cis-cat, compliance-as-code, audit-automation

• Configuration Management — Topic Pack, L1, 1h
  Topics: Configuration Management
  Aliases: configuration-management, config-management, config-drift, infrastructure-as-code

• Containers Deep Dive — Topic Pack, L1, 5h
  Topics: Containers Deep Dive, Docker / Containers, Container Runtimes
  Aliases: containers-internals, overlayfs, oci, buildkit, podman, rootless, docker-internals, container-runtime-debug, runtime-debugging, containers, dockerfile, docker-compose

• Corporate IT Fluency for Engineers — Topic Pack, L0, 3h
  Topics: Corporate IT Fluency, Career Engineering
  Aliases: itsm, itil, cab, cmdb, sla, raci, capex, opex, compliance, soc2, corporate-lingo, enterprise-it

• Corporate It Fluency Flashcards (CLI) — flashcard_deck, L1
  Topics: Corporate IT Fluency
  Aliases: itsm, itil, cab, cmdb, sla, raci, capex, opex, compliance, soc2, corporate-lingo, enterprise-it

• Crossplane — Topic Pack, L2, 3h
  Topics: Crossplane, Terraform
  Aliases: crossplane, k8s-iac, compositions, managed-resources, provider-aws, iac, infrastructure-as-code, hcl, tfstate

• DORA Metrics & DevEx — Topic Pack, L1, 3h
  Topics: DORA Metrics & DevEx
  Aliases: dora, deployment-frequency, lead-time, mttr, change-failure-rate, devex, four-keys

• Dagger / CI as Code — Topic Pack, L2, 2h
  Topics: Dagger / CI as Code, CI/CD
  Aliases: dagger, ci-as-code, pipeline-sdk, portable-ci, continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

• Data Modeling — Topic Pack, L2, 1h
  Topics: Data Modeling
  Aliases: data-modeling, schema-design, data-architecture, normalization

• Database Internals — Topic Pack, L1, 2h
  Topics: Database Internals
  Aliases: db-internals, storage-engine, write-ahead-log, mvcc

• Database Internals Flashcards (CLI) — flashcard_deck, L1
  Topics: Database Internals
  Aliases: db-internals, storage-engine, write-ahead-log, mvcc

• Databases — Topic Pack, L2, 1h
  Topics: Databases
  Aliases: database, rdbms, nosql, database-selection

• Databases Flashcards (CLI) — flashcard_deck, L1
  Topics: SQL
  Aliases: sql, querying, select, databases

• Datascience Flashcards (CLI) — flashcard_deck, L1
  Topics: AI/ML Infrastructure Ops
  Aliases: gpu-scheduling, model-serving, vllm, triton, ml-infrastructure

• Debugging Methodology — Topic Pack, L1, 4h
  Topics: Debugging Methodology, Incident Response, Systems Thinking
  Aliases: systematic-troubleshooting, divide-and-conquer, hypothesis-testing, five-whys, root-cause, incidents, triage, forensics, rca, postmortem, chaos-engineering, feedback-loops

• Debugging Methodology Flashcards (CLI) — flashcard_deck, L1
  Topics: Debugging Methodology
  Aliases: systematic-troubleshooting, divide-and-conquer, hypothesis-testing, five-whys, root-cause

• Deep Dive: CI/CD Pipeline Architecture — deep_dive, L2, 45m
  Topics: CI/CD, GitHub Actions
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul, github-actions, gha, workflows, actions-runner, ci-github

• Deep Dive: Containers How They Really Work — deep_dive, L2, 45m
  Topics: Docker / Containers, Container Runtimes
  Aliases: containers, dockerfile, docker-compose, images, containerd, cri-o, runc, cgroups, namespaces, container-runtime-debug

• Deep Dive: Docker Image Internals — deep_dive, L2, 45m
  Topics: Docker / Containers, Container Image Optimization (alias → container_images)
  Aliases: containers, dockerfile, docker-compose, images, distroless, multi-stage, slim-images, docker-slim, image-security, layer-caching

• Deep Dive: Terraform State Internals — deep_dive, L2, 45m
  Topics: Terraform
  Aliases: iac, infrastructure-as-code, hcl, tfstate

• Deployments — Topic Pack, L1, 1h
  Topics: Deployments
  Aliases: deploy, release-engineering, rolling-update, blue-green, canary-release

• DevOps Learning Roadmap — Reference, L0, 15m

• Devops Flashcards (CLI) — flashcard_deck, L1
  Topics: Postmortems & SLOs
  Aliases: slo, sli, sla, error-budget, postmortem, blameless, devops

• Distributed Systems Fundamentals — Topic Pack, L2, 5h
  Topics: Distributed Systems Fundamentals
  Aliases: cap-theorem, raft, consensus, eventual-consistency, distributed-systems, pacelc, saga-pattern, 2pc

• Edge & IoT Infrastructure — Topic Pack, L2, 4h
  Topics: Edge & IoT Infrastructure, Linux Fundamentals
  Aliases: edge-computing, iot, constrained-devices, ota-updates, remote-fleet, linux, linux-basics, filesystem, permissions

• Edge IoT Flashcards (CLI) — flashcard_deck, L1
  Topics: Edge & IoT Infrastructure
  Aliases: edge-computing, iot, constrained-devices, ota-updates, remote-fleet

• Elasticsearch — Topic Pack, L1, 2h
  Topics: Elasticsearch
  Aliases: elastic, elk, opensearch, search-engine

• Elasticsearch Flashcards (CLI) — flashcard_deck, L1
  Topics: Elasticsearch
  Aliases: elastic, elk, opensearch, search-engine

• Feature Flags — Topic Pack, L1, 3h
  Topics: Feature Flags
  Aliases: feature-flags, openfeature, launchdarkly, flagsmith, trunk-based-development, gradual-rollout

• FinOps & Cost Optimization — Topic Pack, L2, 4h
  Topics: FinOps
  Aliases: cost-optimization, cloud-billing, reserved-instances, spot

• FinOps Drills — Drill, L2, 30m
  Topics: FinOps
  Aliases: cost-optimization, cloud-billing, reserved-instances, spot

• Finops Flashcards (CLI) — flashcard_deck, L1
  Topics: FinOps
  Aliases: cost-optimization, cloud-billing, reserved-instances, spot

• Fleet Operations Flashcards (CLI) — flashcard_deck, L1
  Topics: Fleet Operations
  Aliases: fleet-management, fleet-automation, at-scale, parallel-execution, inventory

• Fleet Operations at Scale — Topic Pack, L2, 5h
  Topics: Fleet Operations, Ansible, Bash / Shell Scripting
  Aliases: fleet-management, fleet-automation, at-scale, parallel-execution, inventory, playbooks, roles, ansible-galaxy, chef, puppet, saltstack, config-management

• Generativeai Flashcards (CLI) — flashcard_deck, L1
  Topics: AI Tools for DevOps
  Aliases: ai, llm, chatgpt, claude, copilot, codex, prompt-engineering, ai-tools, generativeai

• Git Advanced — Topic Pack, L2, 5h
  Topics: Git Advanced, Git, Git Save Your Ass
  Aliases: rebase, cherry-pick, bisect, reflog, worktrees, hooks, submodules, stash, interactive-rebase, version-control, branching, merging

• Git Drills — Drill, L0, 30m
  Topics: Git
  Aliases: version-control, branching, merging, rebase

• Git Flashcards (CLI) — flashcard_deck, L1
  Topics: Git
  Aliases: version-control, branching, merging, rebase

• Git Workflows & Branching Strategies — Topic Pack, L2, 3h
  Topics: Git Workflows & Branching Strategies
  Aliases: branching-strategy, trunk-based, github-flow, gitflow, gitlab-flow, release-branching, branching-model

• Git Workflows Flashcards (CLI) — flashcard_deck, L1
  Topics: Git Workflows & Branching Strategies
  Aliases: branching-strategy, trunk-based, github-flow, gitflow, gitlab-flow, release-branching, branching-model

• Git for DevOps — Topic Pack, L0, 3h
  Topics: Git
  Aliases: version-control, branching, merging, rebase

• GitHub Actions — Topic Pack, L1, 4h
  Topics: GitHub Actions, CI/CD
  Aliases: github-actions, gha, workflows, actions-runner, ci-github, continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

• GitOps — Topic Pack, L1, 2h
  Topics: GitOps
  Aliases: argocd, argo, flux, desired-state, drift-detection

• GitOps & ArgoCD Drills — Drill, L2, 30m
  Topics: GitOps
  Aliases: argocd, argo, flux, desired-state, drift-detection

• Gitops Flashcards (CLI) — flashcard_deck, L1
  Topics: GitOps
  Aliases: argocd, argo, flux, desired-state, drift-detection

• GraphQL — Topic Pack, L2, 4h
  Topics: GraphQL
  Aliases: graphql-api, gql, apollo, relay

• Graphql Flashcards (CLI) — flashcard_deck, L1
  Topics: GraphQL
  Aliases: graphql-api, gql, apollo, relay

• Grokdevops Training Flashcards (CLI) — flashcard_deck, L1
  Topics: Career Engineering
  Aliases: resume, interview-prep, career-strategy, job-search, impact-stories, career-engineering

• HTTP Protocol Flashcards (CLI) — flashcard_deck, L1
  Topics: HTTP Protocol
  Aliases: http, https, web, apis, rest

• Helm Drills — Drill, L1, 30m
  Topics: Helm
  Aliases: helm-charts, helm-upgrade, helm-rollback, values-files

• Helm Flashcards (CLI) — flashcard_deck, L1
  Topics: Helm
  Aliases: helm-charts, helm-upgrade, helm-rollback, values-files

• Homelab & Learning Infrastructure — Topic Pack, L0, 5h
  Topics: Homelab
  Aliases: proxmox, pihole, wireguard, self-hosted, practice-lab, home-server

• Homelab Flashcards (CLI) — flashcard_deck, L1
  Topics: Homelab
  Aliases: proxmox, pihole, wireguard, self-hosted, practice-lab, home-server

• Incident Command & On-Call — Topic Pack, L2, 4h
  Topics: On-Call & Incident Command, Incident Response
  Aliases: pagerduty, opsgenie, incident-commander, escalation, war-room, incident-command, incidents, triage, forensics, rca, postmortem, chaos-engineering

• Incident Psychology Flashcards (CLI) — flashcard_deck, L1
  Topics: Incident Psychology
  Aliases: cognitive-bias, stress-response, communication-under-pressure

• Incident Response Flashcards (CLI) — flashcard_deck, L1
  Topics: Incident Response
  Aliases: incidents, triage, forensics, rca, postmortem, chaos-engineering

• Incident Triage — Topic Pack, L1, 2h
  Topics: Incident Triage
  Aliases: triage, incident-assessment, severity-classification

• Infrastructure Testing — Topic Pack, L2, 4h
  Topics: Infrastructure Testing
  Aliases: terratest, inspec, conftest, rego, policy-as-code, infra-testing, kitchen, kubeconform

• Interview: Config Drift Detected — Scenario, L2, 15m
  Topics: GitOps
  Aliases: argocd, argo, flux, desired-state, drift-detection

• Interview: Cost Spike Investigation — Scenario, L2, 15m
  Topics: FinOps
  Aliases: cost-optimization, cloud-billing, reserved-instances, spot

• Interview: GitOps Drift Detected — Scenario, L2, 15m
  Topics: GitOps
  Aliases: argocd, argo, flux, desired-state, drift-detection

• Interview: Helm Upgrade Broke Prod — Scenario, L2, 15m
  Topics: Helm
  Aliases: helm-charts, helm-upgrade, helm-rollback, values-files

• Jenkins Flashcards (CLI) — flashcard_deck, L1
  Topics: CI/CD
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

• Kafka — Topic Pack, L1, 2h
  Topics: Kafka
  Aliases: message-queue, event-streaming, kafka-connect, kafka-streams

• Kafka Flashcards (CLI) — flashcard_deck, L1
  Topics: Kafka
  Aliases: message-queue, event-streaming, kafka-connect, kafka-streams

• Lab: GitOps Sync and Drift (CLI) — Lab, L2, 30m
  Topics: GitOps
  Aliases: argocd, argo, flux, desired-state, drift-detection

• Lab: Helm Upgrade Rollback (CLI) — Lab, L1, 30m
  Topics: Helm
  Aliases: helm-charts, helm-upgrade, helm-rollback, values-files

• Legacy System Archaeology — Topic Pack, L1, 4h
  Topics: Legacy System Archaeology
  Aliases: inherited-systems, undocumented, reverse-engineering, tribal-knowledge, legacy-archaeology

• Legacy Systems Flashcards (CLI) — flashcard_deck, L1
  Topics: Legacy System Archaeology
  Aliases: inherited-systems, undocumented, reverse-engineering, tribal-knowledge, legacy-archaeology

• Load Testing — Topic Pack, L1, 3h
  Topics: Load Testing
  Aliases: k6, gatling, locust, load-testing, stress-testing, soak-testing, performance-testing

• MLOps Flashcards (CLI) — flashcard_deck, L1
  Topics: AI/ML Infrastructure Ops
  Aliases: gpu-scheduling, model-serving, vllm, triton, ml-infrastructure

• Make & Build Systems — Topic Pack, L1, 3h
  Topics: Make & Build Systems, Bash / Shell Scripting
  Aliases: make, makefile, gnu-make, just, taskfile, build-automation, task-runner, bash, shell, scripting, shell-scripting, advanced-bash

• Mental Models (Core Concepts) — Topic Pack, L0, 4h
  Topics: Mental Models (Core), Linux Fundamentals, Git, Ansible, Kubernetes Core, Docker / Containers, Terraform, CI/CD, Observability Deep Dive, Linux Networking Tools
  Aliases: mental-models, conceptual-models, mental-model-first, linux, linux-basics, filesystem, permissions, version-control, branching, merging, rebase, playbooks

• Mental Models (Core) Flashcards (CLI) — flashcard_deck, L0
  Topics: Mental Models (Core)
  Aliases: mental-models, conceptual-models, mental-model-first

• Mental-Model-First Learning Guide — Reference, L0, 30m
  Topics: Mental Models (Core)
  Aliases: mental-models, conceptual-models, mental-model-first

• Mergerfs Flashcards (CLI) — flashcard_deck, L1
  Topics: mergerfs
  Aliases: merger-fs, fuse-union, trapexit, union-filesystem, jbod-pooling

• Message Queues — Topic Pack, L2, 5h
  Topics: Message Queues
  Aliases: message-queues, rabbitmq, kafka, amqp, pub-sub, event-streaming

• Message Queues Flashcards (CLI) — flashcard_deck, L1
  Topics: Message Queues
  Aliases: message-queues, rabbitmq, kafka, amqp, pub-sub, event-streaming

• MongoDB Operations — Topic Pack, L1, 4h
  Topics: MongoDB Operations
  Aliases: mongodb, mongo, replica-set, sharding, wiredtiger, mongodump, atlas, aggregation-pipeline

• MySQL / MariaDB Operations — Topic Pack, L1, 4h
  Topics: MySQL / MariaDB Operations
  Aliases: mysql, mariadb, innodb, percona, pt-osc, xtrabackup, mysql-replication, proxysql

• NGINX Flashcards (CLI) — flashcard_deck, L1
  Topics: Nginx & Web Servers
  Aliases: nginx, apache, httpd, reverse-proxy, web-server, virtual-hosts

• Nginx & Web Servers — Topic Pack, L1, 5h
  Topics: Nginx & Web Servers, Load Balancing, TLS & PKI
  Aliases: nginx, apache, httpd, reverse-proxy, web-server, virtual-hosts, load-balancer, haproxy, nginx-lb, pki, certificates, x509

• Nix / NixOS — Topic Pack, L2, 4h
  Topics: Nix / NixOS
  Aliases: nix, nixos, nix-flakes, nixpkgs, reproducible-builds, nix-shell

• Observability Flashcards (CLI) — flashcard_deck, L1
  Topics: Observability Deep Dive
  Aliases: observability-deep-dive, o11y-deep-dive

• On Call Flashcards (CLI) — flashcard_deck, L1
  Topics: On-Call & Incident Command
  Aliases: pagerduty, opsgenie, incident-commander, escalation, war-room, incident-command

• On-Call — Topic Pack, L2, 1h
  Topics: On-Call & Incident Command, Alerting Rules
  Aliases: pagerduty, opsgenie, incident-commander, escalation, war-room, incident-command, alertmanager, alert-rules, on-call, alerting-rules

• OpenTofu & Terraform Ecosystem — Topic Pack, L2, 2h
  Topics: OpenTofu & Terraform Ecosystem, Terraform
  Aliases: opentofu, tofu, terraform-fork, bsl, terraform-alternatives, iac, infrastructure-as-code, hcl, tfstate

• Operations War Stories Flashcards (CLI) — flashcard_deck, L1
  Topics: Ops War Stories
  Aliases: pattern-recognition, differential-diagnosis, experience-transfer

• Ops Archaeology: The 5% That Can't Resolve — Case Study, L2, 30m
  Topics: DNS, Kubernetes Networking
  Aliases: domain-name-system, coredns, dig, nslookup, resolve, dns-ops, cni, network-policies, ingress, service-mesh

• Ops Archaeology: The Alerts That Stopped Firing — Case Study, L2, 30m
  Topics: Prometheus, Kubernetes Core
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog, kubernetes, pods, deployments, services, k8s

• Ops Archaeology: The Certificate That Works Sometimes — Case Study, L2, 30m
  Topics: TLS & PKI, Linux Networking Tools
  Aliases: pki, certificates, x509, ca-chain, cert-rotation, ssl, cert-manager, tls, ip-command, ss, tcpdump, ethtool

• Ops Archaeology: The Cluster That Disagrees With Itself — Case Study, L2, 30m
  Topics: Kubernetes Core, Linux Networking Tools
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, ip-command, ss, tcpdump, ethtool, nmcli, mtr

• Ops Archaeology: The Container That Exits Immediately — Case Study, L1, 30m
  Topics: Docker / Containers, Linux Fundamentals
  Aliases: containers, dockerfile, docker-compose, images, linux, linux-basics, filesystem, permissions

• Ops Archaeology: The DR That Looks Ready But Isn't — Case Study, L2, 30m
  Topics: Kubernetes Core, Linux Networking Tools
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, ip-command, ss, tcpdump, ethtool, nmcli, mtr

• Ops Archaeology: The Deploy That Didn't Deploy — Case Study, L1, 30m
  Topics: Kubernetes Core, Docker / Containers
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, containers, dockerfile, docker-compose, images

• Ops Archaeology: The Gateway That Returns 502 — Case Study, L1, 30m
  Topics: Linux Networking Tools, Linux Fundamentals
  Aliases: ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute, linux, linux-basics, filesystem, permissions

• Ops Archaeology: The Job That Succeeded Wrong — Case Study, L2, 30m
  Topics: Kubernetes Core, Linux Fundamentals
  Aliases: kubernetes, pods, deployments, services, k8s, openshift, linux, linux-basics, filesystem, permissions

• Ops Archaeology: The Pods That Won't Schedule — Case Study, L1, 30m
  Topics: Kubernetes Core
  Aliases: kubernetes, pods, deployments, services, k8s, openshift

• Ops Archaeology: The Replica That Fell Behind — Case Study, L2, 30m
  Topics: Linux Fundamentals, Linux Networking Tools
  Aliases: linux, linux-basics, filesystem, permissions, ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute

• Ops Archaeology: The Requests That Vanish — Case Study, L2, 30m
  Topics: Kubernetes Networking, Linux Networking Tools
  Aliases: cni, network-policies, ingress, coredns, service-mesh, ip-command, ss, tcpdump, ethtool, nmcli, mtr, traceroute

• Ops Archaeology: The Service That Won't Start — Case Study, L1, 30m
  Topics: systemd, Linux Fundamentals
  Aliases: systemctl, journalctl, services, units, linux, linux-basics, filesystem, permissions

• Ops Archaeology: The Session Store That Keeps Dying — Case Study, L2, 30m
  Topics: OOMKilled, Kubernetes Core
  Aliases: oom, out-of-memory, resource-limits, memory, kubernetes, pods, deployments, services, k8s, openshift

• Ops Archaeology: The Slow Death Nobody Noticed — Case Study, L2, 30m
  Topics: Linux Fundamentals, Prometheus
  Aliases: linux, linux-basics, filesystem, permissions, metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog

• Ops War Stories & Pattern Recognition — Topic Pack, L2, 4h
  Topics: Ops War Stories, Incident Response
  Aliases: pattern-recognition, differential-diagnosis, experience-transfer, incidents, triage, forensics, rca, postmortem, chaos-engineering

• Performance — Topic Pack, L2, 1h
  Topics: Performance
  Aliases: performance-engineering, performance-tuning, bottleneck-analysis, profiling

• Perl Flashcards (CLI) — flashcard_deck, L1
  Topics: Python Automation
  Aliases: python, scripting, automation, perl, software-development

• Platform Engineering Flashcards (CLI) — flashcard_deck, L1
  Topics: Platform Engineering
  Aliases: internal-developer-platform, idp, golden-path, self-service, developer-experience

• Platform Engineering Patterns — Topic Pack, L2, 5h
  Topics: Platform Engineering, Kubernetes Core, CI/CD
  Aliases: internal-developer-platform, idp, golden-path, self-service, developer-experience, kubernetes, pods, deployments, services, k8s, openshift, continuous-integration

• PostgreSQL Operations — Topic Pack, L2, 4h
  Topics: PostgreSQL Operations, Database Operations
  Aliases: postgres, postgresql, pg, vacuuming, wal, replication-slots, pgbouncer, pg-stat, statefulsets, database, mysql, backup-restore

• Postmortem & SLO Drills — Drill, L2, 30m
  Topics: Postmortems & SLOs
  Aliases: slo, sli, sla, error-budget, postmortem, blameless, devops

• Postmortem SLO Flashcards (CLI) — flashcard_deck, L1
  Topics: Postmortems & SLOs
  Aliases: slo, sli, sla, error-budget, postmortem, blameless, devops

• Postmortems & SLOs — Topic Pack, L2, 4h
  Topics: Postmortems & SLOs, Incident Response
  Aliases: slo, sli, sla, error-budget, postmortem, blameless, devops, incidents, triage, forensics, rca, chaos-engineering

• PowerShell — Topic Pack, L1, 2h
  Topics: PowerShell
  Aliases: pwsh, powershell-core, windows-scripting, powershell-automation

• Prometheus Stack Flashcards (CLI) — flashcard_deck, L1
  Topics: Prometheus Deep Dive
  Aliases: prometheus, promql, alertmanager, scrape, recording-rules, thanos, mimir, servicemonitor

• Pulumi — Topic Pack, L2, 3h
  Topics: Pulumi, Terraform
  Aliases: pulumi, iac-sdk, pulumi-python, pulumi-typescript, infrastructure-sdk, iac, infrastructure-as-code, hcl, tfstate

• Puppet Flashcards (CLI) — flashcard_deck, L1
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Python Async & Concurrency — Topic Pack, L2, 4h
  Topics: Python Async & Concurrency, Python Automation
  Aliases: asyncio, threading, multiprocessing, async-await, GIL, concurrent-futures, aiohttp, python, scripting, automation, perl, software-development

• Python Debugging — Topic Pack, L1, 3h
  Topics: Python Debugging, Python Automation
  Aliases: pdb, debugpy, py-spy, traceback, profiling, cProfile, tracemalloc, ipdb, python, scripting, automation, perl

• Python Drills — Drill, L0, 30m
  Topics: Python Automation
  Aliases: python, scripting, automation, perl, software-development

• Python Exercises (Quest Ladder) (CLI) — Exercise Set, L0, 8h
  Topics: Python Automation
  Aliases: python, scripting, automation, perl, software-development

• Python Flashcards (CLI) — flashcard_deck, L1
  Topics: Python Automation
  Aliases: python, scripting, automation, perl, software-development

• Python Packaging — Topic Pack, L2, 3h
  Topics: Python Packaging, Python Automation
  Aliases: pip, virtualenv, venv, pyproject-toml, poetry, requirements-txt, wheel, setuptools, python, scripting, automation, perl

• Python for Infrastructure — Topic Pack, L1, 5h
  Topics: Python Automation
  Aliases: python, scripting, automation, perl, software-development

• RHCE (EX294) Exam Preparation — Topic Pack, L2, 40h
  Topics: RHCE (EX294) Exam, Ansible, Git, Linux Fundamentals, Bash / Shell Scripting, systemd, SELinux & AppArmor
  Aliases: rhce, ex294, red-hat-certified-engineer, ansible-automation, rhcsa, red-hat, playbooks, roles, inventory, ansible-galaxy, chef, puppet

• RHCE Flashcards (CLI) — flashcard_deck, L1
  Topics: RHCE (EX294) Exam
  Aliases: rhce, ex294, red-hat-certified-engineer, ansible-automation, rhcsa, red-hat

• RabbitMQ & Message Queues — Topic Pack, L2, 3h
  Topics: RabbitMQ & Message Queues, Kafka
  Aliases: rabbitmq, amqp, message-queue, message-broker, celery, dead-letter, event-streaming, kafka-connect, kafka-streams

• Redis Operations — Topic Pack, L2, 3h
  Topics: Redis Operations, Database Operations
  Aliases: redis, redis-cluster, redis-sentinel, caching, eviction-policies, pub-sub, statefulsets, database, mysql, backup-restore

• Reliability Patterns — Topic Pack, L2, 1h
  Topics: Reliability Patterns
  Aliases: reliability-patterns, circuit-breaker, bulkhead, graceful-degradation, fault-tolerance

• Repository Flashcards (CLI) — flashcard_deck, L1
  Topics: Git
  Aliases: version-control, branching, merging, rebase

• Runbook Craft — Topic Pack, L1, 4h
  Topics: Runbook Craft, On-Call & Incident Command, Incident Response
  Aliases: runbook-writing, decision-tree, escalation-docs, operational-docs, pagerduty, opsgenie, incident-commander, escalation, war-room, incident-command, incidents, triage

• Runbook Craft Flashcards (CLI) — flashcard_deck, L1
  Topics: Runbook Craft
  Aliases: runbook-writing, decision-tree, escalation-docs, operational-docs

• Runbook: Ansible Playbook Failure — Runbook, L1, 15m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Runbook: ArgoCD Out of Sync — Runbook, L2, 15m
  Topics: GitOps
  Aliases: argocd, argo, flux, desired-state, drift-detection

• Runbook: Build Failure Triage — Runbook, L1, 15m
  Topics: CI/CD, CI/CD Pipelines Realities
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul, pipeline-realities, cicd-real-world, pipeline-gotchas

• Runbook: Container Registry Pull Failure — Runbook, L1, 15m
  Topics: Docker / Containers, CI/CD
  Aliases: containers, dockerfile, docker-compose, images, continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

• Runbook: Deploy Rollback — Runbook, L1, 15m
  Topics: CI/CD, GitOps
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul, argocd, argo, flux, desired-state, drift-detection

• Runbook: Helm Upgrade Failed — Runbook, L1, 15m
  Topics: Helm
  Aliases: helm-charts, helm-upgrade, helm-rollback, values-files

• Runbook: Long-Running Query / Lock Contention — Runbook, L2, 15m
  Topics: PostgreSQL Operations, Database Locking
  Aliases: postgres, postgresql, pg, vacuuming, wal, replication-slots, pgbouncer, pg-stat, row-lock, table-lock, deadlock, optimistic-locking

• Runbook: Pipeline Stuck / Hung Job — Runbook, L1, 15m
  Topics: CI/CD
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

• Runbook: PostgreSQL Connection Exhaustion — Runbook, L2, 15m
  Topics: PostgreSQL Operations
  Aliases: postgres, postgresql, pg, vacuuming, wal, replication-slots, pgbouncer, pg-stat

• Runbook: PostgreSQL Disk Space Critical — Runbook, L2, 15m
  Topics: PostgreSQL Operations, Filesystems & Storage
  Aliases: postgres, postgresql, pg, vacuuming, wal, replication-slots, pgbouncer, pg-stat, ext4, xfs, btrfs, file-systems

• Runbook: PostgreSQL Replication Lag — Runbook, L2, 15m
  Topics: PostgreSQL Operations, Database Replication
  Aliases: postgres, postgresql, pg, vacuuming, wal, replication-slots, pgbouncer, pg-stat, db-replication, primary-replica, replication-lag

• Runbook: Terraform Drift Detection Response — Runbook, L2, 15m
  Topics: Terraform, Terraform Deep Dive
  Aliases: iac, infrastructure-as-code, hcl, tfstate, terraform-state, terraform-modules, terraform-import, hcl-advanced, remote-state, workspaces

• Runbook: Terraform State Lock Stuck — Runbook, L2, 15m
  Topics: Terraform
  Aliases: iac, infrastructure-as-code, hcl, tfstate

• S3-Compatible Object Storage — Topic Pack, L1, 3h
  Topics: S3-Compatible Object Storage
  Aliases: minio, s3, object-storage, bucket, presigned-url, multipart-upload, ceph-rgw, boto3

• SQL Flashcards (CLI) — flashcard_deck, L1
  Topics: SQL
  Aliases: sql, querying, select, databases

• SQL Fundamentals — Topic Pack, L0, 2h
  Topics: SQL, Database Operations
  Aliases: sql, querying, select, databases, statefulsets, database, mysql, backup-restore

• SQLite Operations & Internals — Topic Pack, L2, 3h
  Topics: SQLite Operations & Internals, Database Operations
  Aliases: sqlite, litestream, litefs, turso, embedded-database, sqlite-wal, statefulsets, database, mysql, backup-restore

• SRE Practices — Topic Pack, L2, 5h
  Topics: SRE Practices, Postmortems & SLOs, Alerting Rules
  Aliases: site-reliability, toil, error-budget, reliability-engineering, capacity-planning, sre-practices, slo, sli, sla, postmortem, blameless, devops

• SSH Hygiene Flashcards (CLI) — flashcard_deck, L1
  Topics: SSH Deep Dive
  Aliases: ssh, sshd, ssh-keygen, ssh-agent, port-forwarding, bastion, jump-host, scp, sftp

• Saltstack Flashcards (CLI) — flashcard_deck, L1
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Skillcheck: Ansible — Assessment, L1, 30m
  Topics: Ansible
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management

• Skillcheck: CI/CD — Assessment, L1, 30m
  Topics: CI/CD
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

• Skillcheck: Cloud Basics — Assessment, L1, 30m

• Skillcheck: DevOps Roadmap (Expanded) — Assessment, L1, 45m

• Skillcheck: FinOps — Assessment, L2, 30m
  Topics: FinOps
  Aliases: cost-optimization, cloud-billing, reserved-instances, spot

• Skillcheck: Git — Assessment, L0, 30m
  Topics: Git
  Aliases: version-control, branching, merging, rebase

• Skillcheck: GitOps — Assessment, L2, 30m
  Topics: GitOps
  Aliases: argocd, argo, flux, desired-state, drift-detection

• Skillcheck: Helm & Release Ops — Assessment, L1, 30m
  Topics: Helm
  Aliases: helm-charts, helm-upgrade, helm-rollback, values-files

• Skillcheck: Postmortems & SLOs — Assessment, L2, 30m
  Topics: Postmortems & SLOs
  Aliases: slo, sli, sla, error-budget, postmortem, blameless, devops

• Skillcheck: Python Automation — Assessment, L0, 30m
  Topics: Python Automation
  Aliases: python, scripting, automation, perl, software-development

• Skillcheck: Terraform / IaC — Assessment, L1, 30m
  Topics: Terraform
  Aliases: iac, infrastructure-as-code, hcl, tfstate

• Software Development Flashcards (CLI) — flashcard_deck, L1
  Topics: Python Automation
  Aliases: python, scripting, automation, perl, software-development

• Systems Thinking Flashcards (CLI) — flashcard_deck, L1
  Topics: Systems Thinking
  Aliases: feedback-loops, emergent-behavior, coupling, cascading-failures, complexity

• Systems Thinking for Engineers — Topic Pack, L1, 4h
  Topics: Systems Thinking, Incident Response
  Aliases: feedback-loops, emergent-behavior, coupling, cascading-failures, complexity, incidents, triage, forensics, rca, postmortem, chaos-engineering

• Terraform / IaC — Topic Pack, L1, 5h
  Topics: Terraform
  Aliases: iac, infrastructure-as-code, hcl, tfstate

• Terraform Basics Flashcards (CLI) — flashcard_deck, L1
  Topics: Terraform
  Aliases: iac, infrastructure-as-code, hcl, tfstate

• Terraform Deep Dive — Topic Pack, L2, 5h
  Topics: Terraform Deep Dive, Terraform
  Aliases: terraform-state, terraform-modules, terraform-import, hcl-advanced, remote-state, workspaces, iac, infrastructure-as-code, hcl, tfstate

• Terraform Drills — Drill, L1, 30m
  Topics: Terraform
  Aliases: iac, infrastructure-as-code, hcl, tfstate

• Terraform Modules Flashcards (CLI) — flashcard_deck, L1
  Topics: Terraform Deep Dive
  Aliases: terraform-state, terraform-modules, terraform-import, hcl-advanced, remote-state, workspaces

• Terraform Providers Flashcards (CLI) — flashcard_deck, L1
  Topics: Terraform Deep Dive
  Aliases: terraform-state, terraform-modules, terraform-import, hcl-advanced, remote-state, workspaces

• Terraform State Flashcards (CLI) — flashcard_deck, L1
  Topics: Terraform Deep Dive
  Aliases: terraform-state, terraform-modules, terraform-import, hcl-advanced, remote-state, workspaces

• Terraform Workflow Flashcards (CLI) — flashcard_deck, L1
  Topics: Terraform Deep Dive
  Aliases: terraform-state, terraform-modules, terraform-import, hcl-advanced, remote-state, workspaces

• The Ops of AI/ML Workloads — Topic Pack, L2, 4h
  Topics: AI/ML Infrastructure Ops, Kubernetes Core, AI Tools for DevOps
  Aliases: gpu-scheduling, model-serving, vllm, triton, ml-infrastructure, kubernetes, pods, deployments, services, k8s, openshift, ai

• The Psychology of Incidents — Topic Pack, L2, 4h
  Topics: Incident Psychology, Incident Response, On-Call & Incident Command
  Aliases: cognitive-bias, stress-response, communication-under-pressure, incidents, triage, forensics, rca, postmortem, chaos-engineering, pagerduty, opsgenie, incident-commander

• Toil Reduction — Topic Pack, L2, 1h
  Topics: Toil Reduction
  Aliases: toil-reduction, toil-elimination, operational-toil

• Topic Tag Cloud & Content Index — Reference, L0, 10m

• Track: Helm & Release Ops — Reference, L1, 8h
  Topics: Helm, GitOps
  Aliases: helm-charts, helm-upgrade, helm-rollback, values-files, argocd, argo, flux, desired-state, drift-detection

• Track: Incident Response — Reference, L2, 10h
  Topics: Incident Response
  Aliases: incidents, triage, forensics, rca, postmortem, chaos-engineering

• Track: Infrastructure — Reference, L1, 12h
  Topics: Ansible, Terraform
  Aliases: playbooks, roles, inventory, ansible-galaxy, chef, puppet, saltstack, config-management, iac, infrastructure-as-code, hcl, tfstate

• VS Code Flashcards (CLI) — flashcard_deck, L1
  Topics: VS Code
  Aliases: visual-studio-code, editor, ide, remote-development, dev-containers

• VS Code for DevOps — Topic Pack, L0, 3h
  Topics: VS Code
  Aliases: visual-studio-code, editor, ide, remote-development, dev-containers

• Vendor Management & Escalation — Topic Pack, L1, 3h
  Topics: Vendor Management & Escalation, On-Call & Incident Command, Incident Response
  Aliases: tac-case, rma, support-tiers, vendor-escalation, support-contracts, pagerduty, opsgenie, incident-commander, escalation, war-room, incident-command, incidents

• Vendor Management Flashcards (CLI) — flashcard_deck, L1
  Topics: Vendor Management & Escalation
  Aliases: tac-case, rma, support-tiers, vendor-escalation, support-contracts

• WebAssembly for Infrastructure — Topic Pack, L3, 3h
  Topics: WebAssembly for Infrastructure
  Aliases: wasm, wasi, spin, wasmcloud, fermyon, wasm-runtime

• Zuul Flashcards (CLI) — flashcard_deck, L1
  Topics: CI/CD
  Aliases: continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

CLI Tools

• CLI Tools Flashcards (CLI) — flashcard_deck, L1
  Topics: Modern CLI Tools
  Aliases: bat, eza, zoxide, dust, modern-unix, cli-tools

• Modern CLI Drills — Drill, L0, 30m
  Topics: Modern CLI Tools, jq / JSON Processing, ripgrep (rg), fzf
  Aliases: bat, eza, zoxide, dust, modern-unix, cli-tools, jq-filters, yq, json, yaml-processing, rg, fast-grep

• Modern CLI Flashcards (CLI) — flashcard_deck, L1
  Topics: Modern CLI Tools
  Aliases: bat, eza, zoxide, dust, modern-unix, cli-tools

• Modern CLI Tools — Topic Pack, L0, 3h
  Topics: jq / JSON Processing, ripgrep (rg), fzf, fd, Modern CLI Tools
  Aliases: jq-filters, yq, json, yaml-processing, rg, fast-grep, code-search, fuzzy-finder, interactive-selection, fd-find, fast-find, file-search

• Modern Cli Workflows — Topic Pack, L1, 1h
  Topics: Modern CLI Workflows
  Aliases: cli-workflows, modern-shell, terminal-workflows

• Regex & Text Wrangling — Topic Pack, L1, 5h
  Topics: Regex & Text Wrangling, Bash / Shell Scripting, Linux Fundamentals
  Aliases: sed, awk, grep, regex, regular-expressions, text-processing, bash, shell, scripting, shell-scripting, advanced-bash, linux

• Regular Expressions Flashcards (CLI) — flashcard_deck, L1
  Topics: Regex & Text Wrangling
  Aliases: sed, awk, grep, regex, regular-expressions, text-processing

• Ripgrep Flashcards (CLI) — flashcard_deck, L1
  Topics: ripgrep (rg)
  Aliases: rg, fast-grep, code-search

• Skillcheck: Modern CLI Tools — Assessment, L0, 30m
  Topics: jq / JSON Processing, ripgrep (rg), fzf, fd, Modern CLI Tools
  Aliases: jq-filters, yq, json, yaml-processing, rg, fast-grep, code-search, fuzzy-finder, interactive-selection, fd-find, fast-find, file-search

• YAML, JSON & Config Formats — Topic Pack, L1, 3h
  Topics: YAML, JSON & Config Formats, jq / JSON Processing
  Aliases: yaml, json, toml, ini, envfile, jq, yq, yamllint, json-schema, config-formats, jq-filters, yaml-processing

• awk: The Record/Field Processor — Topic Pack, L1, 2h
  Topics: awk, Bash / Shell Scripting
  Aliases: gawk, awk-scripting, record-processor, field-processor, bash, shell, scripting, shell-scripting, advanced-bash

• curl & wget — Topic Pack, L1, 3h
  Topics: curl & wget, Linux Fundamentals
  Aliases: curl, wget, http-client, api-testing, httpie, linux, linux-basics, filesystem, permissions

• fd — Topic Pack, L1, 2h
  Topics: fd
  Aliases: fd-find, fast-find, file-search

• fd Flashcards (CLI) — flashcard_deck, L1
  Topics: fd
  Aliases: fd-find, fast-find, file-search

• find — Topic Pack, L1, 3h
  Topics: find, Bash / Shell Scripting
  Aliases: find, file-search, find-exec, locate, directory-search, bash, shell, scripting, shell-scripting, advanced-bash

• fzf — Topic Pack, L1, 2h
  Topics: fzf
  Aliases: fuzzy-finder, interactive-selection

• fzf Flashcards (CLI) — flashcard_deck, L1
  Topics: fzf
  Aliases: fuzzy-finder, interactive-selection

• grep & Regular Expressions — Topic Pack, L1, 4h
  Topics: grep & Regular Expressions, Bash / Shell Scripting
  Aliases: grep, regex, regexp, egrep, ripgrep, rg, ag, pcre, pattern-matching, bash, shell, scripting

• jq — Topic Pack, L1, 2h
  Topics: jq / JSON Processing
  Aliases: jq-filters, yq, json, yaml-processing

• jq Flashcards (CLI) — flashcard_deck, L1
  Topics: jq / JSON Processing
  Aliases: jq-filters, yq, json, yaml-processing

• ripgrep — Topic Pack, L1, 2h
  Topics: ripgrep (rg)
  Aliases: rg, fast-grep, code-search

• sed: The Stream Editor — Topic Pack, L1, 2h
  Topics: sed, Bash / Shell Scripting
  Aliases: gsed, stream-editor, sed-scripting, in-place-edit, bash, shell, scripting, shell-scripting, advanced-bash

• xargs — Topic Pack, L1, 3h
  Topics: xargs, Bash / Shell Scripting
  Aliases: xargs, parallel-exec, pipe-to-args, batch-commands, bash, shell, scripting, shell-scripting, advanced-bash

Observability

• Alerting Flashcards (CLI) — flashcard_deck, L1
  Topics: Alerting Rules
  Aliases: alertmanager, alert-rules, pagerduty, on-call, alerting-rules

• Alerting Rules — Topic Pack, L2, 4h
  Topics: Alerting Rules, Prometheus
  Aliases: alertmanager, alert-rules, pagerduty, on-call, alerting-rules, metrics, promql, service-monitor, monitoring, prometheusstack, datadog

• Alerting Rules Drills — Drill, L2, 30m
  Topics: Alerting Rules, Prometheus
  Aliases: alertmanager, alert-rules, pagerduty, on-call, alerting-rules, metrics, promql, service-monitor, monitoring, prometheusstack, datadog

• Continuous Profiling — Topic Pack, L2, 4h
  Topics: Continuous Profiling
  Aliases: pyroscope, parca, profiling, flame-graphs, cpu-profiling, heap-profiling, continuous-profiling

• Datadog Flashcards (CLI) — flashcard_deck, L1
  Topics: Prometheus
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog

• Grafana Flashcards (CLI) — flashcard_deck, L1
  Topics: Grafana
  Aliases: dashboards, panels, data-sources

• Interview: Loki Logs Disappeared — Scenario, L2, 15m
  Topics: Loki
  Aliases: logs, log-aggregation, promtail, logql

• Interview: Prometheus Target Down — Scenario, L2, 15m
  Topics: Prometheus
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog

• Lab: Loki No Logs (CLI) — Lab, L2, 30m
  Topics: Loki
  Aliases: logs, log-aggregation, promtail, logql

• Lab: Prometheus Target Down (CLI) — Lab, L2, 30m
  Topics: Prometheus, Grafana
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog, dashboards, panels, data-sources

• Log Pipelines — Topic Pack, L2, 5h
  Topics: Log Pipelines, Logging, Loki
  Aliases: fluentd, fluentbit, vector, log-routing, structured-logging, log-management, centralized-logging, log-pipeline, logs, log-aggregation, promtail, logql

• Log Pipelines Flashcards (CLI) — flashcard_deck, L1
  Topics: Log Pipelines
  Aliases: fluentd, fluentbit, vector, log-routing, structured-logging

• LogQL Drills — Drill, L2, 30m
  Topics: Loki
  Aliases: logs, log-aggregation, promtail, logql

• Loki Flashcards (CLI) — flashcard_deck, L1
  Topics: Loki
  Aliases: logs, log-aggregation, promtail, logql

• Monitoring Flashcards (CLI) — flashcard_deck, L1
  Topics: Prometheus
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog

• Monitoring Fundamentals — Topic Pack, L1, 5h
  Topics: Monitoring Fundamentals, Prometheus, Grafana
  Aliases: nagios, zabbix, snmp, cacti, mrtg, legacy-monitoring, checks, metrics, promql, service-monitor, alertmanager, monitoring

• Monitoring Migration (Legacy to Modern) — Topic Pack, L2, 5h
  Topics: Monitoring Migration, Monitoring Fundamentals, Prometheus, Grafana
  Aliases: nagios-to-prometheus, zabbix-migration, monitoring-modernization, nagios, zabbix, snmp, cacti, mrtg, legacy-monitoring, checks, metrics, promql

• Observability Architecture — Reference, L2, 30m
  Topics: Prometheus, Grafana, Loki, Tempo
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog, dashboards, panels, data-sources, logs, log-aggregation

• Observability Deep Dive — Topic Pack, L2, 6h
  Topics: Prometheus, Grafana, Loki, Tempo
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog, dashboards, panels, data-sources, logs, log-aggregation

• Observability Drills — Drill, L2, 30m
  Topics: Prometheus, Loki
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog, logs, log-aggregation, promtail, logql

• OpenTelemetry — Topic Pack, L2, 5h
  Topics: OpenTelemetry, Tracing, Prometheus
  Aliases: otel, otel-collector, instrumentation, unified-observability, distributed-tracing-concepts, trace-propagation, span, metrics, promql, service-monitor, alertmanager, monitoring

• PromQL Drills — Drill, L2, 30m
  Topics: Prometheus
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog

• Prometheus Deep Dive — Topic Pack, L2, 5h
  Topics: Prometheus Deep Dive, Prometheus
  Aliases: prometheus, promql, alertmanager, scrape, recording-rules, thanos, mimir, servicemonitor, metrics, service-monitor, monitoring, prometheusstack

• Runbook: Alert Storm (Flapping / Too Many Alerts) — Runbook, L2, 15m
  Topics: Alerting Rules, Prometheus
  Aliases: alertmanager, alert-rules, pagerduty, on-call, alerting-rules, metrics, promql, service-monitor, monitoring, prometheusstack, datadog

• Runbook: Grafana Dashboard Blank / No Data — Runbook, L1, 15m
  Topics: Grafana
  Aliases: dashboards, panels, data-sources

• Runbook: Log Pipeline Backpressure / Logs Not Appearing — Runbook, L2, 15m
  Topics: Log Pipelines, Loki
  Aliases: fluentd, fluentbit, vector, log-routing, structured-logging, logs, log-aggregation, promtail, logql

• Runbook: Loki No Logs — Runbook, L2, 15m
  Topics: Loki
  Aliases: logs, log-aggregation, promtail, logql

• Runbook: Prometheus Target Down — Runbook, L1, 15m
  Topics: Prometheus
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog

• Runbook: Tempo No Traces — Runbook, L2, 15m
  Topics: Tempo
  Aliases: traces, distributed-tracing, spans

• SLO Tooling — Topic Pack, L2, 4h
  Topics: SLO Tooling
  Aliases: sloth, pyrra, openslo, slo, error-budget, burn-rate, multi-burn-rate, slo-tooling

• Skillcheck: Alerting Rules — Assessment, L2, 30m
  Topics: Alerting Rules, Prometheus
  Aliases: alertmanager, alert-rules, pagerduty, on-call, alerting-rules, metrics, promql, service-monitor, monitoring, prometheusstack, datadog

• Skillcheck: Observability — Assessment, L2, 30m
  Topics: Prometheus, Grafana, Loki, Tempo
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog, dashboards, panels, data-sources, logs, log-aggregation

• Synthetic Monitoring — Topic Pack, L1, 3h
  Topics: Synthetic Monitoring
  Aliases: blackbox-exporter, synthetic-monitoring, checkly, probe, uptime-monitoring, ssl-expiry

• Tempo Flashcards (CLI) — flashcard_deck, L1
  Topics: Tempo
  Aliases: traces, distributed-tracing, spans

• Tracing — Topic Pack, L1, 2h
  Topics: Tracing
  Aliases: distributed-tracing-concepts, trace-propagation, span

• Track: Observability — Reference, L2, 10h
  Topics: Prometheus, Grafana, Loki, Tempo
  Aliases: metrics, promql, service-monitor, alertmanager, monitoring, prometheusstack, datadog, dashboards, panels, data-sources, logs, log-aggregation

Security

• Audit Logging — Topic Pack, L1, 2h
  Topics: Audit Logging
  Aliases: auditd, audit-trail, security-logging

• Audit Logging Flashcards (CLI) — flashcard_deck, L1
  Topics: Audit Logging
  Aliases: auditd, audit-trail, security-logging

• Backup Restore — Topic Pack, L1, 2h
  Topics: Backup & Restore
  Aliases: backup-recovery, disaster-recovery-drill, restore-test, backup

• Backup Restore Flashcards (CLI) — flashcard_deck, L1
  Topics: Backup & Restore
  Aliases: backup-recovery, disaster-recovery-drill, restore-test, backup

• Compliance & Audit Automation — Topic Pack, L2, 5h
  Topics: Compliance & Audit, Linux Hardening, Audit Logging
  Aliases: openscap, inspec, stig, cis-cat, compliance-as-code, audit-automation, os-hardening, cis-benchmark, system-hardening, auditd, audit-trail, security-logging

• Disaster Recovery & Backup Engineering — Topic Pack, L2, 5h
  Topics: Disaster Recovery, Backup & Restore
  Aliases: dr-plan, rto, rpo, failover, backup-strategy, borg, restic, backup-recovery, disaster-recovery-drill, restore-test, backup

• Disaster Recovery Flashcards (CLI) — flashcard_deck, L1
  Topics: Disaster Recovery
  Aliases: dr-plan, rto, rpo, failover, backup-strategy, borg, restic

• HashiCorp Vault — Topic Pack, L2, 4h
  Topics: HashiCorp Vault, Secrets Management
  Aliases: vault, vault-secrets, vault-pki, vault-transit, dynamic-secrets, vault-agent, sealed-secrets, external-secrets, sops

• Incident Triage Flashcards (CLI) — flashcard_deck, L1
  Topics: Incident Triage
  Aliases: triage, incident-assessment, severity-classification

• Infrastructure Forensics — Topic Pack, L2, 5h
  Topics: Infrastructure Forensics, Audit Logging, Linux Hardening
  Aliases: post-breach, rootkit-detection, evidence-preservation, log-forensics, infra-forensics, auditd, audit-trail, security-logging, os-hardening, cis-benchmark, system-hardening

• Interview: CI Vuln Scan Failed — Scenario, L2, 15m
  Topics: Security Scanning, CI/CD
  Aliases: trivy, vulnerability-scan, security, cyber-security, continuous-integration, continuous-delivery, pipelines, jenkins, circleci, zuul

• Interview: Certificate Expired — Scenario, L2, 15m
  Topics: TLS & PKI
  Aliases: pki, certificates, x509, ca-chain, cert-rotation, ssl, cert-manager, tls

• Interview: Secret Leaked to Git — Scenario, L2, 15m
  Topics: Secrets Management, Git
  Aliases: sealed-secrets, external-secrets, sops, version-control, branching, merging, rebase

• Interview: Vault Token Expired — Scenario, L2, 15m
  Topics: Secrets Management
  Aliases: sealed-secrets, external-secrets, sops

• LDAP & Identity Management — Topic Pack, L2, 5h
  Topics: LDAP & Identity Management, Linux Hardening, Least Privilege
  Aliases: ldap, freeipa, active-directory, sssd, pam, kerberos, identity, os-hardening, cis-benchmark, system-hardening, principle-of-least-privilege, access-control

• LDAP Flashcards (CLI) — flashcard_deck, L1
  Topics: LDAP & Identity Management
  Aliases: ldap, freeipa, active-directory, sssd, pam, kerberos, identity

• Lab: Trivy Scan Remediation (CLI) — Lab, L1, 30m
  Topics: Security Scanning, Docker / Containers
  Aliases: trivy, vulnerability-scan, security, cyber-security, containers, dockerfile, docker-compose, images

• Offensive Security Basics — Topic Pack, L1, 2h
  Topics: Offensive Security Basics
  Aliases: pentesting, red-team, offensive-security, ethical-hacking

• Open Policy Agent — Topic Pack, L2, 4h
  Topics: Open Policy Agent
  Aliases: opa, rego, gatekeeper, opa-gatekeeper, policy-engine

• Open Policy Agent Flashcards (CLI) — flashcard_deck, L1
  Topics: Open Policy Agent
  Aliases: opa, rego, gatekeeper, opa-gatekeeper, policy-engine

• Opsec Mistakes — Topic Pack, L1, 2h
  Topics: OpSec Mistakes
  Aliases: operational-security, opsec, common-mistakes

• Runbook: CVE Response (Critical Vulnerability) — Runbook, L2, 20m
  Topics: Security Scanning, Incident Triage
  Aliases: trivy, vulnerability-scan, security, cyber-security, triage, incident-assessment, severity-classification

• Runbook: Certificate Renewal Failed — Runbook, L2, 15m
  Topics: TLS & PKI
  Aliases: pki, certificates, x509, ca-chain, cert-rotation, ssl, cert-manager, tls

• Runbook: Credential Rotation (Exposed Secret) — Runbook, L2, 15m
  Topics: Secrets Management
  Aliases: sealed-secrets, external-secrets, sops

• Runbook: Secret Rotation — Runbook, L2, 15m
  Topics: Secrets Management
  Aliases: sealed-secrets, external-secrets, sops

• Runbook: Unauthorized Access Investigation — Runbook, L2, 20m
  Topics: Incident Triage, Audit Logging
  Aliases: triage, incident-assessment, severity-classification, auditd, audit-trail, security-logging

• Runtime Security with Falco — Topic Pack, L2, 4h
  Topics: Runtime Security with Falco
  Aliases: falco, falcosidekick, runtime-security, kernel-security, ebpf-security, syscall-detection

• SELinux & AppArmor — Topic Pack, L2, 5h
  Topics: SELinux & AppArmor, Linux Hardening, Linux Fundamentals
  Aliases: selinux, apparmor, mac, mandatory-access-control, audit2allow, os-hardening, cis-benchmark, system-hardening, linux, linux-basics, filesystem, permissions

• SELinux & Linux Hardening — Topic Pack, L2, 5h
  Topics: Linux Hardening, Compliance & Audit, Audit Logging
  Aliases: os-hardening, cis-benchmark, system-hardening, openscap, inspec, stig, cis-cat, compliance-as-code, audit-automation, auditd, audit-trail, security-logging

• Secrets Management — Topic Pack, L2, 4h
  Topics: Secrets Management
  Aliases: sealed-secrets, external-secrets, sops

• Secrets Management Drills — Drill, L2, 30m
  Topics: Secrets Management
  Aliases: sealed-secrets, external-secrets, sops

• Secrets Management Flashcards (CLI) — flashcard_deck, L1
  Topics: Secrets Management
  Aliases: sealed-secrets, external-secrets, sops

• Security Basics (Ops-Focused) — Topic Pack, L1, 4h
  Topics: Security Scanning
  Aliases: trivy, vulnerability-scan, security, cyber-security

• Security Drills — Drill, L2, 30m
  Topics: Security Scanning
  Aliases: trivy, vulnerability-scan, security, cyber-security

• Security Flashcards (CLI) — flashcard_deck, L1
  Topics: Security Scanning
  Aliases: trivy, vulnerability-scan, security, cyber-security

• Security Scanning — Topic Pack, L1, 2h
  Topics: Security Scanning
  Aliases: trivy, vulnerability-scan, security, cyber-security

• Selinux Flashcards (CLI) — flashcard_deck, L1
  Topics: SELinux & AppArmor
  Aliases: selinux, apparmor, mac, mandatory-access-control, audit2allow

• Skillcheck: Secrets Management — Assessment, L2, 30m
  Topics: Secrets Management
  Aliases: sealed-secrets, external-secrets, sops

• Skillcheck: Security (Expanded) — Assessment, L2, 30m
  Topics: Security Scanning
  Aliases: trivy, vulnerability-scan, security, cyber-security

• Skillcheck: TLS & PKI — Assessment, L2, 30m
  Topics: TLS & PKI
  Aliases: pki, certificates, x509, ca-chain, cert-rotation, ssl, cert-manager, tls

• Supply Chain Security — Topic Pack, L2, 3h
  Topics: Supply Chain Security
  Aliases: sbom, sigstore, cosign, slsa, software-supply-chain, in-toto, provenance

• TLS & Certificates Ops — Topic Pack, L1, 6h
  Topics: TLS & Certificates Ops, TLS & PKI
  Aliases: tls-ops, certificates, x509, openssl, cert-manager, lets-encrypt, acme, mtls, pem, pki, ca-chain, cert-rotation

• TLS & PKI Drills — Drill, L2, 30m
  Topics: TLS & PKI
  Aliases: pki, certificates, x509, ca-chain, cert-rotation, ssl, cert-manager, tls

Cloud

• AWS CloudWatch — Topic Pack, L2, 4h
  Topics: AWS CloudWatch, Cloud Deep Dive
  Aliases: cloudwatch, cw-logs, cw-metrics, cw-alarms, logs-insights, cloudwatch-agent, synthetics, multi-cloud, iam, vpc, aws, gcp

• AWS Compute Flashcards (CLI) — flashcard_deck, L1
  Topics: AWS EC2
  Aliases: ec2, instances, ami, ebs, auto-scaling, launch-template, spot-instances, instance-types

• AWS Database Flashcards (CLI) — flashcard_deck, L1
  Topics: Database Operations
  Aliases: statefulsets, database, mysql, backup-restore

• AWS Devops Flashcards (CLI) — flashcard_deck, L1
  Topics: Cloud Deep Dive
  Aliases: multi-cloud, iam, vpc, aws, gcp, azure, cloud

• AWS EC2 — Topic Pack, L1, 4h
  Topics: AWS EC2, Cloud Deep Dive
  Aliases: ec2, instances, ami, ebs, auto-scaling, launch-template, spot-instances, instance-types, multi-cloud, iam, vpc, aws

• AWS ECS — Topic Pack, L2, 4h
  Topics: AWS ECS, Cloud Deep Dive, Docker / Containers
  Aliases: ecs, fargate, task-definition, ecs-service, capacity-provider, ecs-exec, firelens, multi-cloud, iam, vpc, aws, gcp

• AWS General Flashcards (CLI) — flashcard_deck, L1
  Topics: Cloud Deep Dive
  Aliases: multi-cloud, iam, vpc, aws, gcp, azure, cloud

• AWS IAM — Topic Pack, L1, 4h
  Topics: AWS IAM, Cloud Deep Dive
  Aliases: iam, aws-iam, iam-roles, iam-policies, sts, assume-role, irsa, service-control-policy, multi-cloud, vpc, aws, gcp

• AWS Lambda — Topic Pack, L2, 3h
  Topics: AWS Lambda, Cloud Deep Dive
  Aliases: lambda, serverless, cold-start, event-driven, function-as-a-service, sam, lambda-layers, multi-cloud, iam, vpc, aws, gcp

• AWS Networking — Topic Pack, L1, 4h
  Topics: AWS Networking, Cloud Deep Dive, TCP/IP
  Aliases: vpc, aws-vpc, security-groups, nacl, nat-gateway, transit-gateway, vpc-peering, privatelink, multi-cloud, iam, aws, gcp

• AWS Networking Flashcards (CLI) — flashcard_deck, L1
  Topics: AWS Networking
  Aliases: vpc, aws-vpc, security-groups, nacl, nat-gateway, transit-gateway, vpc-peering, privatelink

• AWS Route 53 — Topic Pack, L2, 3h
  Topics: AWS Route 53, DNS, Cloud Deep Dive
  Aliases: route53, dns-aws, hosted-zone, alias-record, health-check, failover-routing, domain-name-system, coredns, dig, nslookup, resolve, dns-ops

• AWS S3 Deep Dive — Topic Pack, L1, 4h
  Topics: AWS S3 Deep Dive, Cloud Deep Dive
  Aliases: s3, buckets, objects, lifecycle, versioning, s3-encryption, presigned-url, multipart-upload, multi-cloud, iam, vpc, aws

• AWS Security Flashcards (CLI) — flashcard_deck, L1
  Topics: AWS IAM
  Aliases: iam, aws-iam, iam-roles, iam-policies, sts, assume-role, irsa, service-control-policy

• AWS Storage Flashcards (CLI) — flashcard_deck, L1
  Topics: AWS S3 Deep Dive
  Aliases: s3, buckets, objects, lifecycle, versioning, s3-encryption, presigned-url, multipart-upload

• AWS Troubleshooting — Topic Pack, L1, 2h
  Topics: AWS Troubleshooting
  Aliases: aws-debug, aws-issues, aws-ops

• AWS Troubleshooting Flashcards (CLI) — flashcard_deck, L1
  Topics: AWS Troubleshooting
  Aliases: aws-debug, aws-issues, aws-ops

• Azure Flashcards (CLI) — flashcard_deck, L1
  Topics: Cloud Deep Dive
  Aliases: multi-cloud, iam, vpc, aws, gcp, azure, cloud

• Azure Troubleshooting — Topic Pack, L1, 2h
  Topics: Azure Troubleshooting
  Aliases: azure-debug, azure-issues, azure-ops

• Azure Troubleshooting Flashcards (CLI) — flashcard_deck, L1
  Topics: Azure Troubleshooting
  Aliases: azure-debug, azure-issues, azure-ops

• Cloud Deep Dive — Topic Pack, L2, 5h
  Topics: Cloud Deep Dive
  Aliases: multi-cloud, iam, vpc, aws, gcp, azure, cloud

• Cloud Deep Dive Drills — Drill, L2, 30m
  Topics: Cloud Deep Dive
  Aliases: multi-cloud, iam, vpc, aws, gcp, azure, cloud

• Cloud Flashcards (CLI) — flashcard_deck, L1
  Topics: Cloud Deep Dive
  Aliases: multi-cloud, iam, vpc, aws, gcp, azure, cloud

• Cloud Ops Drills — Drill, L1, 30m
  Topics: Cloud Deep Dive
  Aliases: multi-cloud, iam, vpc, aws, gcp, azure, cloud

• GCP Compute Flashcards (CLI) — flashcard_deck, L1
  Topics: GCP Troubleshooting
  Aliases: gcp-debug, gcp-issues, gcp-ops

• GCP General Flashcards (CLI) — flashcard_deck, L1
  Topics: GCP Troubleshooting
  Aliases: gcp-debug, gcp-issues, gcp-ops

• GCP Kubernetes Flashcards (CLI) — flashcard_deck, L1
  Topics: GCP Troubleshooting
  Aliases: gcp-debug, gcp-issues, gcp-ops

• GCP Networking Flashcards (CLI) — flashcard_deck, L1
  Topics: GCP Troubleshooting
  Aliases: gcp-debug, gcp-issues, gcp-ops

• GCP Security Flashcards (CLI) — flashcard_deck, L1
  Topics: GCP Troubleshooting
  Aliases: gcp-debug, gcp-issues, gcp-ops

• GCP Troubleshooting — Topic Pack, L1, 2h
  Topics: GCP Troubleshooting
  Aliases: gcp-debug, gcp-issues, gcp-ops

• GCP Troubleshooting Flashcards (CLI) — flashcard_deck, L1
  Topics: GCP Troubleshooting
  Aliases: gcp-debug, gcp-issues, gcp-ops

• Runbook: Cloud Capacity Limit Hit — Runbook, L2, 15m
  Topics: Cloud Deep Dive, Terraform
  Aliases: multi-cloud, iam, vpc, aws, gcp, azure, cloud, iac, infrastructure-as-code, hcl, tfstate

• Runbook: VPC IP Exhaustion — Runbook, L2, 15m
  Topics: Cloud Deep Dive
  Aliases: multi-cloud, iam, vpc, aws, gcp, azure, cloud

• Serverless Computing — Topic Pack, L2, 1h
  Topics: Serverless Computing
  Aliases: faas, function-as-a-service, scale-to-zero, cloud-functions

• Skillcheck: Cloud Providers — Assessment, L1, 30m
  Topics: Cloud Deep Dive
  Aliases: multi-cloud, iam, vpc, aws, gcp, azure, cloud

containers

• Docker Basics Flashcards (CLI) — flashcard_deck, L1
  Topics: Docker / Containers
  Aliases: containers, dockerfile, docker-compose, images

• Docker Networking Flashcards (CLI) — flashcard_deck, L1
  Topics: Kubernetes Networking
  Aliases: cni, network-policies, ingress, coredns, service-mesh

• Docker Operations Flashcards (CLI) — flashcard_deck, L1
  Topics: Docker / Containers
  Aliases: containers, dockerfile, docker-compose, images

• Docker Security Flashcards (CLI) — flashcard_deck, L1
  Topics: Containers Deep Dive
  Aliases: containers-internals, overlayfs, oci, buildkit, podman, rootless, docker-internals, container-runtime-debug, runtime-debugging

• Docker Storage Flashcards (CLI) — flashcard_deck, L1
  Topics: Containers Deep Dive
  Aliases: containers-internals, overlayfs, oci, buildkit, podman, rootless, docker-internals, container-runtime-debug, runtime-debugging