DHCP option 82 configuration

DHCP option 82 is enabled when you enable DHCP snooping on a VLAN. There are no additional configuration steps to enable DHCP option 82. Refer to Configuring DHCP snooping to enable DHCP snooping.

When processing DHCP packets the FastIron switch applies the following default behavior when DHCP option 82 is enabled:

  • Subjects all ports in the VLAN to DHCP option 82 processing
  • Uses the general CID packet format
  • Uses the standard RID packet format
  • Replaces relay agent information received in DHCP packets with its own information
  • Does not enable SID processing

When DHCP option 82 is enabled, you can optionally:

  • Disable DHCP option 82 processing on individual ports in the VLAN
  • Configure the device to drop or keep the relay agent information in a DHCP packet instead of replacing it with its own information
  • Configure Subscriber ID (SID), Circuit ID (CID) or Remote ID (RID) processing.
Parent topic: DHCP relay agent information and option 82 insertion