CLI Reference Guide-R04

Chapter 31 | IP Interface Commands
IPv4 Interface
– 902 –
Command Usage
◆ The ARP cache is used to map 32-bit IP addresses into 48-bit hardware (i.e.,
Media Access Control) addresses. This cache includes entries for hosts and
other routers on local network interfaces defined on this router.
◆ The maximum number of static entries allowed in the ARP cache is 32.
◆ 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 nor deleted when power is reset. A static
entry can only be removed through the configuration interface.
Example
Console(config)#arp 10.1.0.19 01-02-03-04-05-06
Console(config)#
Related Commands
clear arp-cache (904)
show arp (904)
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
◆ Proxy ARP allows a non-routing device to determine the MAC address of a host
on another subnet or network.
◆ 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.