Use the Tools > ARP (Configure General) page to enable Proxy ARP for specific VLAN interfaces.
Enables or disables Proxy ARP for specified VLAN interfaces, allowing a non-routing device to determine the MAC address of a host on another subnet or network. (Default: Disabled)
When a node in the attached subnetwork does not have routing or a default gateway configured, Proxy ARP can be used to forward ARP requests to a remote subnetwork. When the router receives an ARP request for a remote network and Proxy ARP is enabled, it determines if it has the best route to the remote network, and then answers the ARP request by sending its own MAC address to the requesting node. That node then sends traffic to the router, which in turn uses its own routing table to forward the traffic to the remote destination.
End stations that require Proxy ARP must view the entire network as a single network. These nodes must therefore use a smaller subnet mask than that used by the router or other relevant network devices.
Extensive use of Proxy ARP can degrade router performance because it may lead to increased ARP traffic and increased search time for larger ARP address tables.
For devices that do not respond to ARP requests or do not respond in a timely manner, traffic will be dropped because the IP address cannot be mapped to a physical address. If this occurs, use the Tools > ARP (Configure Static Address - Add) page to manually map an IP address to the corresponding physical address in the ARP cache.
Command Usage
The ARP cache is used to map 32-bit IP addresses into 48-bit hardware (that is, Media Access Control) addresses. This cache includes entries for hosts and other routers on local network interfaces defined on this router.
You can define up to 128 static entries in the ARP cache.
A static entry may need to be used if there is no response to an ARP broadcast message. For example, some applications may not respond to ARP requests or the response arrives too late, causing network operations to time out.
Static entries will not be aged out or deleted when power is reset. You can only remove a static entry via the configuration interface.
Static entries are only displayed on the Show page for VLANs that are up. In other words, static entries are only displayed when configured for the IP subnet of a configure VLAN, and that VLAN is linked up.
Command Parameters
IP address statically mapped to a physical MAC address. (Valid IP addresses consist of four numbers, 0 to 255, separated by periods.)
MAC address statically mapped to the corresponding IP address. (Valid MAC addresses are hexadecimal numbers in the format: xx-xx-xx-xx-xx-xx or xxxxxxxxxxxx)
Use the Tools > ARP (Show Information - ARP Addresses) page to display dynamic or local entries in the ARP cache. The ARP cache contains entries for local interfaces, including subnet, host, and broadcast addresses. However, most entries will be dynamically learned through replies to broadcast messages.
Use the IP > ARP (Show Information - Statistics) page to display statistics for ARP messages crossing all interfaces on this switch.