`dhcpv4-snooping option 82`

Syntax

dhcpv4-snooping option 82 [remote-id {mac | subnet-ip | mgmt-ip}]
                          [untrusted-policy {drop | keep | replace}] 

no dhcpv4-snooping option 82

Description

Configures the addition of option 82 DHCP relay information to DHCP client packets that are being forwarded on trusted ports. DHCP relay is enabled by default.

In the switch default state and when this command is entered without parameters (dhcpv4-snooping option 82), this default configuration is used:

dhcpv4-snooping option 82 remote-id mac untrusted-policy drop

When remote-id is omitted, its default (mac) is used. When untrusted-policy is omitted, its default (drop) is used.

The no form of this command disables DHCPv4 snooping option 82.

Command context

config

Parameters

remote-id

Specifies what address to use as the remote ID for the replace option of untrusted-policy. Specify one of these address types:

mac: The default. Uses the switch MAC address as the remote ID.
subnet-ip: Uses the IP address of the client VLAN as the remote ID.
mgmt-ip: Uses the management interface IP address as the remote ID.

untrusted-policy

Specifies what action to take for DHCP packets (with option 82) that are received on untrusted ports. Specify one of these actions:

drop: The default. Drop DHCP packets (with option 82) without forwarding them.
keep: Forward DHCP packets (with option 82).
replace: Replace the option 82 information in the DHCP packets with whatever is set for remote-id (one of: mac, subnet-ip, or mgmt-ip) and forward the packets.

Authority

Administrators or local user group members with execution rights for this command.

Examples

Configuring DHCPv4 snooping option 82 with the keep action:

switch(config)# dhcpv4-snooping option 82 untrusted-policy keep

Configuring DHCPv4 snooping option 82 with mgmt-ip as the remote-id and the replace action:

switch(config)# dhcpv4-snooping option 82 remote-id mgmt-ip untrusted-policy replace

Disabling DHCPv4 snooping option 82:

switch(config)# no dhcpv4-snooping option 82