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Cisco IE 2000 Switch Software Configuration Guide
OL-25866-01
Chapter 7 Performing Switch Administration
Information About Performing Switch Administration
You can add and remove static addresses and define the forwarding behavior for them. The forwarding
behavior defines how a port that receives a packet forwards it to another port for transmission. Because
all ports are associated with at least one VLAN, the switch acquires the VLAN ID for the address from
the ports that you specify. You can specify a different list of destination ports for each source port.
A packet with a static address that arrives on a VLAN where it has not been statically entered is flooded
to all ports and not learned.
You add a static address to the address table by specifying the destination MAC unicast address and the
VLAN from which it is received. Packets received with this destination address are forwarded to the
interface specified with the interface-id option.
When you configure a static MAC address in a private-VLAN primary or secondary VLAN, you should
also configure the same static MAC address in all associated VLANs. Static MAC addresses configured
in a private-VLAN primary or secondary VLAN are not replicated in the associated VLAN. For more
information about private VLANs, see Chapter 19, “Configuring Private VLANs.”
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:
• 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.
• If you add a unicast MAC address as a static address and configure unicast MAC address filtering,
the switch either adds the MAC address as a static address or drops packets with that MAC address,
depending on which command was entered last. The second command that you entered overrides the
first command.
For example, if you enter the mac address-table static mac-addr vlan vlan-id interface
interface-id global configuration command followed by the mac address-table static mac-addr
vlan vlan-id drop command, the switch drops packets with the specified MAC address as a source
or destination.
If you enter the mac address-table static mac-addr vlan vlan-id drop global configuration
command followed by the mac address-table static mac-addr vlan vlan-id interface interface-id
command, the switch adds the MAC address as a static address.
You enable unicast MAC address filtering and configure the switch to drop packets with a specific
address by specifying the source or destination unicast MAC address and the VLAN from which it is
received.