Configuring Stacking Trunks in a Live Environment

To create or modify a trunk in a production environment, use the multi-stack-trunk command. The multi-stack-trunk command is used to ensure that a stack trunk is formed on two directly connected stack units at the same time. The multi-stack-trunk command can only be enabled on the active controller unit.

By configuring a multi-stack-trunk on two sets of connected stack ports, a trunk-to-port connection is avoided. A trunk-to-port connection is formed when one side of the ports forms a trunk, and the other side of the ports does not. A trunk-to-port connection can result in dropped packets and can potentially break a stacking link.

The following example shows a trunk being formed between stack units 1 and 2 and another trunk being formed between stack units 2 and 3.

ICX7250-48P Router(config)# stack unit 1
ICX7250-48P Router(config-unit-1)# multi-stack-trunk 1/2/3 to 1/2/4 and 2/2/1 to 2/2/2
ICX7250-48P Router(config-unit-1)# stack unit 2
ICX7250-48P Router(config-unit-2)# multi-stack-trunk 2/2/3 to 2/2/4 and 3/2/1 to 3/2/2

Use the no form of the multi-stack-trunk command to remove the stacking trunk configuration.