configure iparp add proxy

configure iparp add proxy [ipNetmask | ip_addr {mask}] {vr vr_name} {mac | vrrp} {always}

Description

Configures the switch to respond to ARP requests on behalf of devices that are incapable of doing so.

Syntax Description

ipNetmask Specifies an IP address/mask length.
ip_addr Specifies an IP address.
mask Specifies a subnet mask.
vr_name Specifies a VR name.
mac Specifies a MAC address to use in the ARP reply.
vrrp Specifies a MAC address to use in the ARP reply. For VLANs running VRRP (Virtual Router Redundancy Protocol), the switch replies with the VRRP virtual MAC. For non-VRRP VLANs, the switch replies with the switch MAC.
always Specifies that the switch responds regardless of the VLAN (Virtual LAN) that the request arrives from.

Default

If you do not specify a VR or VRF, the current VR context is used.

Usage Guidelines

When mask is not specified, an address with the mask 255.255.255.255 is assumed. When neither mac nor vrrp is specified, the MAC address of the switch is used in the ARP response. When always is specified, the switch answers ARP requests without filtering requests that belong to the same subnet of the receiving router interface.

After IP ARP is configured, the system responds to ARP requests on behalf of the device as long as the following conditions are satisfied:

  • The valid IP ARP request is received on a router interface.
  • The target IP address matches the IP address configured in the proxy ARP table.
  • The source IP address is not on the same subnet as the target address (unless the always flag is set).

After all the proxy ARP conditions have been met, the switch formulates an ARP response using the configured MAC address in the packet.

The default maximum number of proxy entries is 256, but can be increased to 4096 by using the following command:

configure iparp max_proxy_entries {vr vr_name}max_proxy_entries

Example

The following example configures the switch to answer ARP requests for all devices with the address range of 100.101.45.1 to 100.101.45.255:

configure iparp add proxy 100.101.45.0/24

History

This command was first available in ExtremeXOS 10.1.

Platform Availability

This command is available on the Summit X450-G2, X460-G2, X670-G2, X770, and ExtremeSwitching X440-G2, X620, X690, X870 series switches.