23.4.2 Configuration of the standby link function

Points to note

The standby link functionality is used to enable a channel group, and to set the maximum number of active ports in the channel group. In addition, either link-down mode or link-not-down mode can be set. The standby link functionality is available only when static link aggregation is used.

Standby ports are set on a port priority basis, whereby a port with a lower priority level is selected for a standby link earlier. Note that the smaller the port priority value, the higher its priority.

Command examples

1. (config)# interface port-channel 10

   Switches channel group 10 to port channel interface configuration mode.

2. (config-if)# channel-group max-active-port 3

   Enables the standby link functionality for channel group 10, and sets the maximum number of active ports in the channel group to 3. Channel group 10 operates in link-down mode.

3. (config-if)# exit

   Returns to global configuration mode.

4. (config)# interface port-channel 20

   (config-if)# channel-group max-active-port 1 no-link-down

   (config-if)# exit

   Changes the mode to port channel interface configuration mode for channel group 20, enables the standby link functionality for the channel group, sets the maximum number of active ports to 1, and sets link-not-down mode.

5. (config)# interface gigabitethernet 1/0/1

   (config-if)# channel-group 20 mode on

   (config-if)# lacp port-priority 300

   Adds port 1/0/1 to channel group 20, and sets the port priority value to 300. Note that a smaller port priority value indicates a higher priority. Therefore, a port with the port priority value of 300, which is larger than the default value of 128, is selected for a standby link earlier than a port with the default priority.