ip dhcp smart-relay

Setting the Gateway Address of the DHCP Broadcast to a Secondary Address Using Smart Relay Agent Forwarding

Perform this task to configure smart relay agent forwarding.

ip dhcp smart-relay

ip dhcp smart-relay

我的理解：接口下有两个地址情况下，如果使用了ip dhcp smart-relay,首先使用primary的地址，如果连续三次发送DHCP request都没有收到DHCP offer的回应，就使用secondary.

假设没有ip dhcp smart-relay，那就一直用primary地址，而不会用secondary地址转发UDP广播包。

如果所有接口下只有一个地址，ip dhcp smart-relay没有意义。

This functionality is useful when the DHCP server cannot be configured to use secondary pools.

SUMMARY STEPS

1. enable

2. configure terminal

3. ip dhcp smart-relay