Configuring Unicast Mac Address Filtering - Cisco Catalyst 2928 Software Configuration Manual

Managing the MAC Address Table
Beginning in privileged EXEC mode, follow these steps to add a static address:
Command
Step 1
configure terminal
Step 2
mac address-table static mac-addr
vlan vlan-id interface interface-id
Step 3
end
Step 4 show mac address-table static
Step 5 copy running-config startup-config
To remove static entries from the address table, use the no mac address-table static mac-addr vlan
vlan-id [interface interface-id] global configuration command.
This example shows how to add the static address c2f3.220a.12f4 to the MAC address table. When a
packet is received in VLAN 4 with this MAC address as its destination address, the packet is forwarded
to the specified port:
Switch(config)# mac address-table static c2f3.220a.12f4 vlan 4 interface
gigabitethernet0/1

Configuring Unicast MAC Address Filtering

When unicast MAC address filtering is enabled, the switch drops packets with specific source or
destination MAC addresses. This feature is disabled by default and only supports unicast static
addresses.
Follow these guidelines when using this feature:
•
•
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Purpose
Enter global configuration mode.
Add a static address to the MAC address table.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
Multicast MAC addresses, broadcast MAC addresses, and router MAC addresses are not supported.
If you specify one of these addresses when entering the mac address-table static mac-addr vlan
vlan-id drop global configuration command, one of these messages appears:
% Only unicast addresses can be configured to be dropped
% CPU destined address cannot be configured as drop address
Packets that are forwarded to the CPU are also not supported.
For mac-addr, specify the destination MAC unicast address to add to
•
the address table. Packets with this destination address received in the
specified VLAN are forwarded to the specified interface.
• For vlan-id, specify the VLAN for which the packet with the
specified MAC address is received. Valid VLAN IDs are 1 to 4094.
For interface-id, specify the interface to which the received packet is
•
forwarded. Valid interfaces include physical ports or port channels.
For static multicast addresses, you can enter multiple interface IDs.
For static unicast addresses, you can enter only one interface at a
time, but you can enter the command multiple times with the same
MAC address and VLAN ID.
Chapter 7 Administering the Switch
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