trunk-threshold

Configures the threshold value for the number of active member ports in a LAG, below which all the ports in a LAG group are disabled.
Syntax
trunk-thresholdnumber
no trunk-thresholdnumber
Command Default

The trunk threshold is set to 1.

Parameters
number

Specifies the number of ports as the threshold number. You can specify a threshold from 1 (the default) up to the number of ports in the LAG group.

Modes

LAG configuration mode

Usage Guidelines

When a LAG is shut down because the number of ports drops below the configured threshold, the LAG is kept intact and it is re-enabled if enough ports become active to reach the threshold.

Note: The trunk-threshold command cannot be used in conjunction with protected link groups.
Note: The trunk-threshold command is only applicable for the configuration of static LAGs.

The trunk-threshold command should be configured only at one end of the LAG. If it is set on both ends, link failures will result in race conditions and the LAG not function properly. Use a short LACP timeout when setting the trunk-threshold value equal to the number of links in the LAG or connecting to third-party devices.

The no form of the command removes the trunk-threshold configuration.

Examples

The following example shows how to establish a LAG group consisting of four ports, and then establish a threshold for this LAG group of three ports. If the number of active ports drops below three, then all the ports in the LAG group are disabled.

device# configure terminal
device(config)# lag blue static
device(config-lag-blue)# ports ethernet 1/3/1 to 1/3/4
device(config-lag-blue)# trunk-threshold 3