Changing the IP Address Used for Stamping BootP and DHCP Requests

When a Layer 3 switch forwards a BootP or DHCP request, the Gateway Address field is "stamped".
The default value the Layer 3 switch uses to stamp the packet is the lowest-numbered IP address configured on the interface that received the request. If you want the Layer 3 switch to use a different IP address to stamp requests received on the interface, use either of the following methods to specify the address.

The BootP/DHCP stamp address is an interface parameter. You can change the parameter on the interface that is connected to the BootP/DHCP client.

  1. Enter global configuration mode. 
    device# configure terminal
  2. Configure an Ethernet interface. 
    device(config)# interface ethernet 1/1/1
  3. Change the BootP or DHCP stamp address for requests received on port 1/1/1 to 10.157.22.26. 
    device(config-if-1/1/1)# ip bootp-gateway 10.157.22.26
    The previous example changes the BootP or DHCP stamp address for requests received on port 1/1/1 to 10.157.22.26. The Layer 3 device places this IP address in the Gateway Address field of BootP or DHCP requests that the Layer 3 device receives on port 1/1/1 and forwards to the BootP or DHCP server.

The following example changes the BootP or DHCP stamp address. 

device# configure terminal
device(config)# interface ethernet 1/1/1
device(config-if-1/1/1)# ip bootp-gateway 10.157.22.26
Parent topic: DHCP Clients