You can configure whether the switch replies to ARP requests on a specified VLAN by proxy ARP if the route to the IP address is reachable, or only if proxy ARP entries have been created.
If an ARP request is received by the switch, it checks the ExtremeXOS proxy ARP table (user adds the entries through the CLI). If it is present, an ARP reply is sent. If not present, it searches for the entry in the kernel route table. If this IP address is reachable, then the ARP reply is sent. The default behavior is for the switch to reply to ARP requests on the specified VLAN(s) by proxy ARP only if proxy ARP entries have been created.
The following table summarizes the this feature's behavior:
|
reachable |
entry-required (or command not configured) |
|
|---|---|---|
| Entry present in proxy ARP Table (static entry added through command configure iparp add ip_addr {vr vr_name} mac ) | Reply to ARP request | Reply to ARP request |
| Static entry not present in proxy ARP table | Reply to ARP request if route is reachable | No reply to ARP request |
| No static entry, but route reachable. | Reply to ARP request | |
| No static entry and route is not reachable | No reply to ARP request | |
| Static entry present and route is reachable | Reply to ARP request | |
| No static entry and route is not reachable | No reply to ARP request | |
| Route reachable | Reply to ARP request | |
| Route not reachable | No reply to ARP request |
ExtremeSwitching X450-G2, X460-G2, X670-G2, X465, X590, X620, X690, X695, X870, 5420, 5520 series switches.
To configure proxy ARP support for reachable routes, use the command:
configure iparp proxy [vlan all | {vlan} vlan_name] [reachable | entry-required]
To view the status for proxy ARP reachable routes on a VLAN, use the command:
show vlan {virtual-router vr-name}