Lacp System-Priority - Cisco Catalyst 3560X-24P Command Reference Manual

Chapter 2 Catalyst 3750-X and 3560-X 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
12.2(53)SE2
Usage Guidelines The lacp system-priority command determines which switch in an LACP link controls port priorities.
An LACP channel group can have up to 16 Ethernet ports of the same type. Up to eight ports can be active,
and up to eight ports can be in standby mode. When there are more than eight ports in an LACP
channel-group, the switch on the controlling end of the link uses port priorities to determine which ports
are bundled into the channel and which ports are put in hot-standby mode. Port priorities on the other
switch (the noncontrolling end of the link) are ignored.
In priority comparisons, numerically lower values have higher priority. Therefore, the system with the
numerically lower value (higher priority value) for LACP system priority becomes the controlling system. If
both switches have the same LACP system priority (for example, they are both configured with the
default setting of 32768), the LACP system ID (the switch MAC address) determines which switch is in
control.
The lacp system-priority command applies to all LACP EtherChannels on the switch.
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 in the output display).
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.
OL-21522-02
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-X and 3560-X Switch Command Reference
lacp system-priority
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