In this post, we will look at how to lookup a mac address on a Cisco switch.

List dynamic MAC addresses
Switch#show mac address-table dynamic Mac Address Table ------------------------------------------- Vlan Mac Address Type Ports ---- ----------- -------- ----- 10 0050.7966.6801 DYNAMIC Gi1/3 10 0050.7966.6802 DYNAMIC Gi0/1 10 0050.7966.6803 DYNAMIC Gi0/2 20 0050.7966.6804 DYNAMIC Gi0/3 20 0050.7966.6805 DYNAMIC Gi1/0 20 0050.7966.6807 DYNAMIC Gi1/1 Total Mac Addresses for this criterion: 6
List MAC addresses on a specific VLAN
Switch#show mac address-table dynamic vlan 10 Mac Address Table ------------------------------------------- Vlan Mac Address Type Ports ---- ----------- -------- ----- 10 0050.7966.6801 DYNAMIC Gi1/3 10 0050.7966.6802 DYNAMIC Gi0/1 10 0050.7966.6803 DYNAMIC Gi0/2 Total Mac Addresses for this criterion: 3 Switch# Switch# Switch#show mac address-table dynamic vlan 20 Mac Address Table ------------------------------------------- Vlan Mac Address Type Ports ---- ----------- -------- ----- 20 0050.7966.6804 DYNAMIC Gi0/3 20 0050.7966.6805 DYNAMIC Gi1/0 20 0050.7966.6807 DYNAMIC Gi1/1 Total Mac Addresses for this criterion: 3
Address to lookup in the table
Switch#show mac address-table dynamic address 0050.7966.6804 Mac Address Table ------------------------------------------- Vlan Mac Address Type Ports ---- ----------- -------- ----- 20 0050.7966.6804 DYNAMIC Gi0/3 Total Mac Addresses for this criterion: 1
List MAC addresses on a specific interface
Switch#show mac address-table dynamic interface Gi0/3 Mac Address Table ------------------------------------------- Vlan Mac Address Type Ports ---- ----------- -------- ----- 20 0050.7966.6804 DYNAMIC Gi0/3 Total Mac Addresses for this criterion: 1
Number of MAC addresses in the table
Switch#show mac address-table count Mac Entries for Vlan 1: --------------------------- Dynamic Address Count : 0 Static Address Count : 0 Total Mac Addresses : 0 Mac Entries for Vlan 10: --------------------------- Dynamic Address Count : 3 Static Address Count : 0 Total Mac Addresses : 3 Mac Entries for Vlan 20: --------------------------- Dynamic Address Count : 3 Static Address Count : 0 Total Mac Addresses : 3 Total Mac Address Space Available: 70013688
Clear all dynamic entry type by address, interface, VLAN, or all
Switch#clear mac address-table dynamic ? address address keyword interface interface keyword vlan vlan keyword <cr>
List of interface status with useful information
Switch#show interfaces status Port Name Status Vlan Duplex Speed Type Gi0/0 notconnect 10 auto auto unknown Gi0/1 connected 10 auto auto unknown Gi0/2 connected 10 auto auto unknown Gi0/3 connected 20 auto auto unknown Gi1/0 connected 20 auto auto unknown Gi1/1 connected 20 auto auto unknown Gi1/2 notconnect 1 auto auto unknown Gi1/3 connected 10 auto auto unknown