Stack Member Priority Values

Cisco EtherSwitch Service Modules Feature Guide

Information About the Cisco EtherSwitch Service Modules

Anew, out-of-the-box Cisco EtherSwitch service module (one that has not joined a switch stack or has not been manually assigned a stack member number) ships with a default stack member number of 1. When it joins a switch stack, its default stack member number changes to the lowest available member number in the stack.

Stack members in the same switch stack cannot have the same stack member number. Every stack member, including a standalone Cisco EtherSwitch service module, retains its member number until you manually change the number or unless the number is already being used by another member in the stack.

•If you manually change the stack member number by using the switch current-stack-member-numberrenumber new-stack-member-numberglobal configuration command, the new number goes into effect after that stack member resets (or after you use the reload slot stack-member-numberprivileged EXEC command) and only if that number is not already assigned to any other members in the stack. Another way to change the stack member number is by changing the SWITCH_NUMBER environment variable.

If the number is being used by another member in the stack, the Cisco EtherSwitch service module or switch selects the lowest available number in the stack.

Note If you manually change the number of a stack member and no interface-level configuration

is associated with that new member number, that stack member resets to its default configuration. For more information about stack member numbers and configurations, see the “Switch Stack Configuration Files” section on page 18.

•If you move a stack member to a different switch stack, the stack member retains its number only if the number is not being used by another member in the stack. If it is being used by another member in the stack, the Cisco EtherSwitch service module or switch selects the lowest available number in the stack.

•If you merge switch stacks, the modules that join the switch stack of a new stack master select the the lowest available numbers in the stack. For more information about merging switch stacks, see the “Accessing the CLI of a Specific Stack Member” section on page 20.

A higher-priority value for a stack member increases its likelihood to be elected stack master and to retain its stack member number. The priority value can be 1 to 15. The default priority value is 1. You can display the stack member priority value by using the show switch user EXEC command.

Note We recommend assigning the highest-priority value to the Cisco EtherSwitch service module or switch that you prefer to be the stack master. This ensures that the Cisco EtherSwitch service module is re-elected as stack master if a re-election occurs.

You can change the priority value for a stack member by using the switch stack-member-numberpriority priority-numberglobal configuration command. Another way to change the member priority value is by changing the SWITCH_PRIORITY environment variable.

The new priority value takes effect immediately but does not affect the current stack master. The new priority value helps determine which stack member is elected as the new stack master when the current stack master or the switch stack resets.

Cisco IOS Release 12.2(25)SEC