Dell EMC SmartFabric OS10 User Guide Release 10.5.0

• enable—Enables preemption on the port channel.
• disable—Disables preemption on the port channel.

When you enable preemption, the fallback port election preempts the already elected fallback port and elects a new fallback port.

The new port is elected based on the following events:

• When a nonfallback port is configured with low priority.
• When a low-priority port becomes operationally UP.
• When a port with the least numbering is operationally UP.
• If nondefault LACP port priority is configured on a port even though preemption is disabled, aport with the lowest priority is elected as fallback port,
• The lacp fallback preemption disable command is not applicable on port priority events that you have configured or triggered.

OS10# configure terminal
OS10(config)# interface port-channel 1
OS10(conf-if-po-1)# lacp fallback preemption enable

OS10# configure terminal
OS10(config)# interface port-channel 1
OS10(conf-if-po-1)# lacp fallback preemption disable