Allied Telesis AlliedWare Plus Operating System Version 5.4.4C (x310-26FT,x310-26FP,x310-50FT,x310-50FP) - Manual (Page 1709)

Dynamic Host Configuration Protocol (DHCP) Commands
Software Reference for x310 Series Switches
C613-50046-01 REV A AlliedWare Plus TM Operating System - Version 5.4.4C 64.11
ip dhcp-relay agent-option checking
This command enables the DHCP Relay Agent to check DHCP Relay Agent Information
Option (Option 82) information in response packets returned from DHCP servers. If the
information does not match the information it has for its own client (downstream)
interface then the DHCP Relay Agent drops the packet. Note that
ip dhcp-relay
agent-option must be configured.
The DHCP Relay Agent Option 82 field is included in relayed client DHCP packets if:
■ DHCP Relay Agent Option 82 is enabled ( ip dhcp-relay agent-option ), and
■ DHCP Relay Agent is enabled on the switch ( service dhcp-relay )
For DHCP Relay Agent and DHCP Relay Agent Option 82 introductory information, see
“DHCP Relay Agent Introduction” on page 63.7 .
Syntax ip dhcp-relay agent-option checking
no ip dhcp-relay agent-option checking
Mode Interface Configuration for a VLAN interface.
Examples To make the DHCP Relay Agent listening on vlan10 check the DHCP Relay Agent
Information Option (Option 82) field, use the commands:
To stop the DHCP Relay Agent on vlan10 from checking the DHCP Relay Agent
Information Option (Option 82) field, use the commands:
Related Commands ip dhcp-relay agent-option
ip dhcp-relay agent-option remote-id
ip dhcp-relay information policy
service dhcp-relay
awplus# configure terminal
awplus(config)# interface vlan10
awplus(config-if)# ip dhcp-relay agent-option
awplus(config-if)# ip dhcp-relay agent-option checking
awplus# configure terminal
awplus(config)# interface vlan10
awplus(config-if)# no ip dhcp-relay agent-option checking