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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
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Chapter 42 Configuring IP Unicast Routing Configuring IP Addressing
To remove an entry from the ARP cache, use the no arp ip-address hardware-address type global
configuration command. To remove all nonstatic entries from the ARP cache, use the clear arp-cache
privileged EXEC command.
Set ARP Encapsulation
By default, Ethernet ARP encapsulation (represented by the arpa keyword) is enabled on an IP interface.
You can change the encapsulation methods to SNAP if required by your network.
Beginning in privileged EXEC mode, follow these steps to specify the ARP encapsulation type:
To disable an encapsulation type, use the no arp arpa or no arp snap interface configuration command.
Step 3 arp ip-address hardware-address type [alias](Optional) Specify that the switch respond to ARP requests as if
it were the owner of the specified IP address.
Step 4 interface interface-id Enter interface configuration mode, and specify the interface to
configure.
Step 5 arp timeout seconds (Optional) Set the length of time an ARP cache entry will stay in
the cache. The default is 14400 seconds (4 hours). The range is
0 to 2147483 seconds.
Step 6 end Return to privileged EXEC mode.
Step 7 show interfaces [interface-id]Verify the type of ARP and the timeout value used on all
interfaces or a specific interface.
Step 8 show arp
or
show ip arp
View the contents of the ARP cache.
Step 9 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 interface interface-id Enter interface configuration mode, and specify the Layer 3
interface to configure.
Step 3 arp {arpa | snap}Specify the ARP encapsulation method:
arpa—Address Resolution Protocol
snap—Subnetwork Address Protocol
Step 4 end Return to privileged EXEC mode.
Step 5 show interfaces [interface-id]Verify ARP encapsulation configuration on all interfaces or
the specified interface.
Step 6 copy running-config startup-config (Optional) Save your entries in the configuration file.