Configure the DHCPv4 Relay Gateway Address

When the DHCP relay agent forwards a Bootstrap Protocol or DHCP request, the relay agent sets the Gateway Address field (GIADDR) of the packet with the address you configure.

About this task

Consider the following when you configure the DHCPv4 relay gateway address.

If the relay gateway address is configured, but no IP address is configured on the interface, the DHCP relay agent does not relay the requests.
When the relay gateway address matches an IP address that is configured on the interface, it is used to stamp the request.
When the relay gateway address does not match the IP addresses configured on the interface, the DHCP relay agent uses the default value, which is the lowest-numbered IP address configured on the interface.
Virtual IP addresses or local subnet broadcast addresses must not be used as the relay gateway address.
Any primary or secondary IP address configured on the interface can be used as the relay gateway address.

Procedure

Access global configuration mode.
```
device# configure terminal
```
Access interface configuration mode.
```
device(config)# interface ethernet 1/4
```
Enter the IP address to be used in the Gateway Address field of Bootstrap Protocol or DHCP requests received on a Layer 3 interface.
```
device(config-if-eth-1/4)# ip dhcp relay gateway 10.50.22.26
```
The relay agent places the IP address 10.50.22.26 in the Gateway Address field of Bootstrap Protocol or DHCP requests that the router receives on port 1/4 and forwards to the BootP or DHCP server.