C
HAPTER
44
| IP Interface Commands
IP Interface
– 1013 –
COMMAND MODE
Global Configuration
COMMAND USAGE
â—† When a ARP entry expires, it is deleted from the cache and an ARP
request packet is sent to re-establish the MAC address.
â—† The aging time determines how long dynamic entries remain in the
cache. If the timeout is too short, the router may tie up resources by
repeating ARP requests for addresses recently flushed from the table.
EXAMPLE
This example sets the ARP cache timeout for 15 minutes (i.e., 900
seconds).
Console(config)#arp timeout 900
Console(config)#
ip proxy-arp This command enables proxy Address Resolution Protocol (ARP). Use the
no form to disable proxy ARP.
SYNTAX
[no] ip proxy-arp
DEFAULT SETTING
Disabled
COMMAND MODE
Interface Configuration (VLAN)
COMMAND USAGE
â—† Proxy ARP allows a non-routing device to determine the MAC address of
a host on another subnet or network.
â—† 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.
â—† 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.
EXAMPLE
Console(config)#interface vlan 3
Console(config-if)#ip proxy-arp
Console(config-if)#