Quiz: Disaster Recovery¶
4 questions
L0 (1 questions)¶
1. Explain the 3-2-1 backup rule and give a concrete example of how to implement it for a production database.
Show answer
3 copies of data, 2 different storage media, 1 offsite copy. Example: Copy 1 is the live production database. Copy 2 is a borg repository on a local backup server (different host/disk). Copy 3 is a restic backup to an offsite S3 bucket. This protects against single-site disasters, single-media failures, and ensures recoverability even if the primary datacenter is lost.L1 (1 questions)¶
1. What is the difference between RPO and RTO, and how do they drive backup strategy?
Show answer
RPO (Recovery Point Objective): how much data you can afford to lose — determines backup frequency. RTO (Recovery Time Objective): how long you can be down — determines recovery method. RPO < 1 hour requires real-time replication. RPO < 24 hours allows daily backups. RTO < 1 hour requires hot standby. RTO < 24 hours allows cold restore from backup.L2 (1 questions)¶
1. Why is 'we have backups' not the same as 'we have disaster recovery'?
Show answer
Backups are only one component. DR requires: tested restore procedures (untested backups are hopes, not backups), documented RTO/RPO per service, verified backup integrity (automated restore tests), offsite copies (local backups die with the server), encryption on offsite copies, and regular DR drills. If you have never restored from your backups, you do not know if they work.L3 (1 questions)¶
1. Compare borg and restic for backup engineering. When would you choose each?