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Questions: DHCP Not Working on Remote VLAN

  • Is ip helper-address configured on the VLAN 50 SVI/interface on the router?
  • If configured, does the helper-address point to the correct DHCP server IP?
  • Does the DHCP server have a scope/pool defined for the VLAN 50 subnet?
  • Can you see DHCPDISCOVER packets on VLAN 50 (tcpdump on a host or mirror port)?
  • Are DHCPDISCOVER packets reaching the router interface?
  • Does the DHCP server log show any incoming requests from the VLAN 50 subnet?
  • Is there an ACL on the router blocking UDP ports 67/68?
  • Is the DHCP server's firewall allowing relay traffic (unicast UDP 67 from the router)?
  • How is DHCP relay configured on the other working VLANs (20, 30, 40) for comparison?