Configuring Additional ARP Features for Multi-VRF
Proxy ARP allows a Layer 3 switch to answer ARP requests from devices on one subnet on behalf of devices in another network. Proxy ARP is configured globally and can be further configured per interface. Interface-level configuration overrides the global configuration.
With the
proxy-arp command configured, a router does not respond to ARP requests for IP addresses in
the same subnet as the incoming ports. The
local-proxy-arp command permits the router to respond to ARP requests for IP addresses within the
same subnet and to forward all traffic between hosts in the subnet. The
local-proxy-arp command is an interface-level configuration that has no VRF-related impact.
ARP rate limiting is configured globally and applies to all VRFs.
ARP age can be configured globally and on a Layer 3 interface. An ARP age timer configured on a Layer 3 interface overrides the global configuration for ARP aging. The aging timer ensures that the ARP cache does not retain learned entries that are no longer valid.
The following example configures proxy ARP globally.
device# configure terminal device(config)# proxy-arp
The following example configures ARP on a Layer 3 Ethernet interface.
device# configure terminal device(config)# interface ethernet 1/7/1 device(config-if-e1000-1/7/1)# local-proxy-arp
The following example configures ARP rate limiting globally.
device# configure terminal device(config)# rate-limit-arp