Cisco Catalyst 2000 Configuration Handbook page 87

66 Cisco LAN Switching Configuration Handbook
Note Depending on your hardware switching platform, the hashing option can vary. See
the following link for additional information: http://www.tinyurl.com/2o44ew.
(Optional) Use LACP on an EtherChannel.
4.
a. Set the system priority:
b. Set the port priority for individual ports:
c. Group ports by setting their administrative keys (automated).
(global) lacp system-priority {value}
Specifies the priority of the system for LACP. The higher the number, the lower
the priority.
The valid range for value is from 1 to 65535. The default is 32768. A LACP sys-
tem priority is configured on each router running LACP. The system priority can
be configured automatically or through the CLI. LACP uses the system priority
with the router MAC address to form the system ID and also during negotiation
with other systems. The LACP system ID is the combination of the LACP system
priority value and the MAC address of the router.
(interface) lacp port-priority {
This command specifies the priority for the physical interface. The valid range
for value is from 1 to 65535. The higher the number, the lower the priority. A
LACP port priority is configured on each port using LACP. The port priority can
be configured automatically or through the CLI. LACP uses the port priority
with the port number to form the port identifier. The port priority determines
which ports should be put in standby mode when a hardware limitation prevents
all compatible ports from aggregating.
Ports that have the potential to become an EtherChannel should have their
administrative key, admin-key (1 to 65535), set to the same value. Up to eight
ports can be assigned the same administrative key value. Ports that have a unique
value are considered to be individual ports and do not become part of an
EtherChannel.
By default, each group of four consecutive ports in a module has the same
unique key value. Key values are only locally significant. However, ports with the
same key value on one switch can potentially form an EtherChannel with ports
sharing another common key value on another switch.
If the admin-key value is not specified, the switch selects an unused, unique
value for the ports listed. If you do specify a key value and that value is already
in use, the ports already assigned are moved to another unique key value.
value}