dhcp relay check mac-address

Use dhcp relay check mac-address to enable MAC address check on the relay agent.

Use undo dhcp relay check mac-address to disable MAC address check on the relay agent.

Syntax

dhcp relay check mac-address

undo dhcp relay check mac-address

Default

The MAC address check feature is disabled.

Views

Interface view

Predefined user roles

network-admin

Usage guidelines

This feature enables the DHCP relay agent to compare the chaddr field of a received DHCP request with the source MAC address in the frame header. If they are the same, the DHCP relay agent forwards the request to the DHCP server. If they are not the same, the DHCP relay agent discards the request.

The MAC address check feature takes effect only when the dhcp select relay command has already been configured on the interface.

Enable the MAC address check feature only on the DHCP relay agent directly connected to the DHCP clients. A DHCP relay agent changes the source MAC address of DHCP packets before sending them. If you enable this feature on an intermediate relay agent, it might discard valid DHCP packet, and the sending clients will not obtain IP addresses.

Examples

# Enable MAC address check on the relay agent.

<Sysname> system-view
[Sysname] interface vlan-interface 10
[Sysname-Vlan-interface10] dhcp relay check mac-address

Related commands

dhcp select relay