Cisco Catalyst 2950 - Configuring Static Addresses for Etherchannel Port Groups

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Catalyst 2950 Desktop Switch Software Configuration Guide
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Chapter 6 Configuring the System
Managing the MAC Address Tables
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 interface-id... global configuration command.
Configuring Static Addresses for EtherChannel Port Groups
Follow these rules if you are configuring a static address to forward to ports in an EtherChannel port
group:
• For default source-based port groups, configure the static address to forward to all ports in the port
group to eliminate lost packets.
• For destination-based port groups, configure the address to forward to only one port in the port
group to avoid the transmission of duplicate packets.
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
mac-address-table static mac-addr vlan
vlan-id interface interface-id 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;
do not enter leading zeroes.
• For interface-id..., specify the interface to which the received
packet is forwarded. Valid interfaces include physical ports and
EtherChannel port-channels. Multiple interfaces can be specified
for multicast addresses.
Step 3
end Return to privileged EXEC mode.
Step 4
show mac-address-table static Verify your entry.