show mac address-table is a Cisco IOS command that displays a switch’s MAC address table. The output identifies each MAC address, VLAN, learning type, and interface where the address was learned. Use it from user EXEC or privileged EXEC mode. section 6.3.3
SW1# show mac address-table #1
Mac Address Table
-------------------------------------------
Vlan Mac Address Type Ports
---- ----------- -------- -----
1 5254.0017.7cd2 DYNAMIC Gi0/0 #2
1 d8bb.c1cc.ff01 DYNAMIC Gi0/1 #2
1 d8bb.c1cc.ff02 DYNAMIC Gi0/2 #2
1 d8bb.c1cc.ff03 DYNAMIC Gi0/0 #2
1 d8bb.c1cc.ff04 DYNAMIC Gi0/0 #2
#1 Views SW1’s MAC address table
#2 A list of MAC addresses and the port each was learned on
A representative SW1 listing shows dynamic MAC addresses associated with VLAN 1 and specific GigabitEthernet interfaces. section 6.3.3
Read the main columns as follows:
- Vlan identifies the VLAN in which the address was learned. section 6.3.3
- Type distinguishes dynamically learned addresses from statically configured addresses. section 6.3.3
- Ports identifies the interface associated with each address; Cisco IOS commonly abbreviates GigabitEthernet as GiX/X. section 6.3.3
Clear dynamic entries
Use clear mac address-table dynamic to remove dynamically learned addresses, then run show mac address-table again to verify the table is empty. Specific addresses or interfaces can also be cleared. section 6.3.3 section 6.6
