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Catalyst 2940 Switch Software Configuration Guide
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Chapter6 Administering the Swi tc h Managing the MAC Address Table
Adding and Removing Static Address Entries
A static address has these characteristics:
•It is manually entered in the address table and must be manually removed.
•It can be a unicast or multicast address.
•It does not age and is retained when the switch restarts.
You can add and remove static addresses and define the forwarding behavior for them. The forwarding
behavior determines 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 static address in one VLAN must be a static address in other VLANs. 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 address (unicast or
multicast) 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.
Beginning in privileged EXEC mode, follow these steps to add a static address:
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 packets isforwarded
to the specified interface:
Switch(config)# mac address-table static c2f3.220a.12f4 vlan 4 interface
gigabitethernet0/1
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 mac address-table static mac-addr
vlan vlan-id interface interface-id Add a static address to the MAC address table.
•For mac-addr, specify the destination MAC address (unicast or
multicast) 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 1005.
•For interface-id..., specify the interface to which the received packet
is forwarded. Valid interfaces include physical ports.
Step3 end Return to privileged EXEC mode.
Step4 show mac address-table static Verify your entries.
Step5 copy running-config startup-config (Optional) Save your entries in the configuration file.