Lacp System-Priority - Cisco Catalyst 3750 Command Reference Manual

Chapter 2 Catalyst 3750 Switch Cisco IOS Commands

lacp system-priority

Use the lacp system-priority global configuration command on the switch stack or on a standalone
switch to configure the system priority for the Link Aggregation Control Protocol (LACP). Use the no
form of this command to return to the default setting.
Syntax Description
priority
Defaults The default is 32768.
Command Modes Global configuration
Command History Release
12.1(14)EA1
Usage Guidelines
Although this is a global configuration command, the priority takes effect only on EtherChannels that
have physical ports that are already configured for LACP.
The software assigns to every link between systems that operate LACP a unique priority made up of the
system priority, system ID, port priority, and the port number. In priority comparisons, numerically lower
values have higher priority. The switch uses the priority to decide which ports should be put in standby
mode when there is a hardware limitation that prevents all compatible ports from aggregating.
Ports are considered for active use in aggregation in link-priority order, starting with the port attached
to the highest priority link. Each port is selected for active use if the preceding higher priority selections
can also be maintained. Otherwise, the port is selected for standby mode. Use the show etherchannel
summary privileged EXEC command to see which ports are in the hot-standby mode (denoted with an
H port-state flag).
The lower the priority, the more likely that the port will be used for LACP transmission.
For more information about configuring LACP on physical ports, see the "Configuring EtherChannels"
chapter in the software configuration guide for this release.
Examples This example shows how to set the LACP system priority:
Switch(config)# lacp system-priority 20000
You can verify your settings by entering the show lacp sys-id privileged EXEC command.
78-16181-03
lacp system-priority priority
no lacp system-priority
System priority for LACP. The range is 1 to 65535.
Modification
This command was introduced.
Catalyst 3750 Switch Command Reference
lacp system-priority
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