3Com WX2200 3CRWX220095A Switch User Manual

Managing the ARP
The Address Resolution Protocol (ARP) table maps IP addresses to MAC
addresses. An ARP entry enters the table in one of the following ways:
Added automatically by the WX switch. A switch adds an entry for its
own MAC address and adds entries for addresses learned from traffic
received by the WX switch. When the WX switch receives an IP
packet, the switch adds the packet’s source MAC address and source
IP address to the ARP table.
Added by the system administrator. You can add dynamic, static, and
permanent entries to the ARP table.
ARP is enabled by default on a WX switch and cannot be disabled.
Displaying ARP Table
To display ARP table entries, use the following command:
display arp [ip-addr]
Here is an example:
WX1200# display arp
ARP aging time: 1200 seconds
Host HW Address VLAN Type State
------------------------------ ----------------- ----- ------- -------- 00:0b:0e:02:76:f5 1 DYNAMIC RESOLVED 00:0b:0e:02:76:f7 1 LOCAL RESOLVED
This example shows two entries. The local entry (with LOCAL in the Type
field) is for the WX switch itself. The MAC address of the local entry is the
switch’s MAC address. The ARP table contains one local entry for each
VLAN configured on the switch. The dynamic entry is learned from traffic
received by the switch. The ARP table can also contain static and
permanent entries, which are added by an administrator. The State field
indicates whether an entry is resolved (RESOLVED) or whether MSS has
sent an ARP request for the entry and is waiting for the reply