Specifications

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Cisco MWR 2941 Mobile Wireless Edge Router Release 3.5 Software Configuration Guide, Cisco IOS Release 15.1(3)MR
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Chapter 12 Managing the MAC Address Table
Displaying Address Table Entries
• You cannot disable MAC address learning on a VLAN that is used internally by the router. If the
VLAN ID that you enter is an internal VLAN, the switch generates an error message and rejects the
command. To view internal VLANs in use, enter the show vlan internal usage privileged EXEC
command.
• If you disable MAC address learning on a VLAN that includes a secure port, MAC address learning
is not disabled on that port.
Beginning in privileged EXEC mode, follow these steps to disable MAC address learning on a VLAN:
To reenable MAC address learning on an interface or VLAN, use the default mac address-table
learning global configuration command. You can also reenable MAC address learning on a VLAN by
entering the mac address-table learning global configuration command. The first (default) command
returns to a default condition and therefore does not appear in the output from the show running-config
command. The second command causes the configuration to appear in the show running-config
privileged EXEC command display.
This example shows how to disable MAC address learning on VLAN 200:
Router(config)# no mac address-table learning vlan 200
This example shows how to disable MAC-address learning for all modules on a specific routed interface:
Router(config)# no mac-address-table learning interface GigabitEthernet 0/5
Router(config)#
You can display the MAC address learning status of all VLANs or a specified VLAN by entering the
show mac-address-table learning [vlan vlan-id] privileged EXEC command.
Displaying Address Table Entries
You can display the MAC address table by using one or more of the privileged EXEC commands
described in Table 12-1:
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
no mac-address-table learning {vlan
vlan-id [,vlan-id | -vlan-id] | interface
interface slot/port}
Disable MAC address learning on an interface or on a specified VLAN or
VLANs.
You can specify a single VLAN ID or a range of VLAN IDs separated by
a hyphen or comma. Valid VLAN IDs 1 to 4094. It cannot be an internal
VLAN.
Step 3
end Return to privileged EXEC mode.
Step 4
show mac address-table learning [vlan
vlan-id | interface interface slot/port]
Verify the configuration.
Step 5
copy running-config startup-config (Optional) Save your entries in the configuration file.
Table 12-1 Commands for Displaying the MAC Address Table
Command Description
show mac address-table address Displays MAC address table information for the specified MAC address.
show mac address-table aging-time Displays the aging time in all VLANs or the specified VLAN.