Technical Documentation

Configuring Proxy ARP (CLI Procedure)

You can configure proxy Address Resolution Protocol (ARP) on your EX Series switch to enable the switch to respond to ARP queries for network addresses by offering its own media access control (MAC) address. With proxy ARP enabled, the switch captures and routes traffic to the intended destination.

To configure proxy ARP on a single interface:

[edit interfaces]
user@switch# set ge-0/0/3 unit 0 proxy-arp restricted

Best Practice: We recommend that you configure proxy ARP in restricted mode. In restricted mode, the switch is not a proxy if the source and target IP addresses are on the same subnet. If you use unrestricted mode, disable gratuitous ARP requests on the interface to avoid the situation of the switch’s response to a gratuitous ARP request appearing to the host to be an indication of an IP conflict:

To configure proxy ARP on a routed VLAN interface (RVI):

[edit interfaces]
user@switch# set vlan unit 100 proxy-arp restricted

Published: 2010-01-14