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Software Configuration Guide—Release 12.2(25)SG
OL-7659-03
Chapter5 Checking Port Status and Conne ctivity
Displaying MAC Addresses
Displaying MAC Addresses
In addition to displaying the MAC address range for a module using the show module command, you
can display the MAC address table information of a specific MAC address or a specific interface in the
switch using the show mac-address-table address and show mac-address-table interface commands.
This example shows how to display MAC address table information for a specific MAC address:
Switch# show mac-address-table address 0050.3e8d.6400
vlan mac address type protocol qos ports
-----+---------------+--------+---------+---+--------------------------------
200 0050.3e8d.6400 static assigned -- Switch
100 0050.3e8d.6400 static assigned -- Switch
5 0050.3e8d.6400 static assigned -- Switch
4 0050.3e8d.6400 static ipx -- Switch
1 0050.3e8d.6400 static ipx -- Switch
1 0050.3e8d.6400 static assigned -- Switch
4 0050.3e8d.6400 static assigned -- Switch
5 0050.3e8d.6400 static ipx -- Switch
100 0050.3e8d.6400 static ipx -- Switch
200 0050.3e8d.6400 static ipx -- Switch
100 0050.3e8d.6400 static other -- Switch
200 0050.3e8d.6400 static other -- Switch
5 0050.3e8d.6400 static other -- Switch
4 0050.3e8d.6400 static ip -- Switch
1 0050.3e8d.6400 static ip -- Route
1 0050.3e8d.6400 static other -- Switch
4 0050.3e8d.6400 static other -- Switch
5 0050.3e8d.6400 static ip -- Switch
200 0050.3e8d.6400 static ip -- Switch
100 0050.3e8d.6400 static ip -- Switch
Switch#
This example shows how to display MAC address table information for a specific interface:
Switch# show mac-address-table interface gigabit 1/1
Multicast Entries
vlan mac address type ports
-------+---------------+-------+-------------------------------------------
1 ffff.ffff.ffff system Switch,Gi6/1,Gi6/2,Gi6/9,Gi1/1
Switch#
Checking Cable Status Using TDR
You can use the Time Domain Reflectometer (TDR) feature to determine if cabling is at fault when you
cannot establish a link.
Note This test is especially important when replacing an existing switch, upgrading to Gigabit Ethernet, or
installing new cable plants.