Stack ID

The stack ID (0–8) identifies a stack member and is a slot ID of the member. Each stack member must have a stack ID that is unique in the stack.

Displaying Stack IDs

Log in to a stack, and view stack IDs by using the display stack command. The Slot field in the command output displays the stack ID of a stack member.
After a stack is established successfully, determine the stack ID of a stack member based on service port indicators. For details, see Displaying Stack IDs Through Service Port Indicators.

Assignment

A new switch, a switch that has not joined a stack, or a switch that has not been manually assigned a stack ID ships with a default stack ID of 0. In a stack, the master switch manages stack IDs of stack members. If a new member switch joins the stack and its stack ID conflicts with that of another member, the master switch searches for the lowest available stack ID and assigns it to the new member switch. If stack IDs are not manually configured before stack setup, stack members are assigned random stack IDs. The stack IDs are assigned based on the stack members' startup sequence when a new stack is set up or when stack members change. You are advised to configure stack IDs for stack members before setting up a stack or perform certain operations to ensure that stack members use planned stack IDs after they start.

If the stack is an AS of an SVF system, method 2 will affect AS login and logout. Therefore, method 1 and method 3 are recommended.

If the stack IDs of some stack members are not 0, method 3 cannot ensure that the actual stack IDs are the planned IDs. Therefore, method 1 and method 2 are recommended.

In a new stack, the following stack ID assignment methods are available.

Method 1	Method 2	Method 3
Configure stack IDs for stack members before setting up a stack. Place member switches. Change the stack IDs of stack members to the expected values. Connect stack members using stack cables.	Set up a stack and then change stack IDs for stack members. Place member switches. Connect stack members using stack cables. Log in to the stack to change the stack IDs of stack members to the expected values and then restart the stack members.	Power on stack members in a certain sequence to make them use the expected stack IDs. Place member switches. Connect stack members using stack cables. Power on stack members one by one.

In a stack requiring capacity expansion, the following stack ID assignment methods are available.

Method 1	Method 2	Method 3
Configure stack IDs for stack members before capacity expansion. Place stack members, log in to the stack, and configure stack IDs for new stack members. Power off the new stack members and then connect them to the stack using stack cables. Power on the new stack members.	Add the new stack members to the stack and then change the stack IDs of the switches. Place member devices. Connect new stack members to the stack using stack cables, and power on the new stack members, which then join the stack and obtain auto-negotiated stack IDs. Log in to the stack to change the stack IDs of the new stack members to the expected values and then restart these switches.	Connect new stack members using cables and then power on these switches. Place member devices. Connect the new stack members to the stack using cables. Power on the new stack members one by one.

After a stack member is removed from a stack, the stack member retains its stack ID. Run the stack slot slot-id renumber new-slot-id command to restore the stack ID to the default value 0. Otherwise, the stack member is assigned the lowest available stack ID after it joins another stack and its stack ID is being used by a stack member in this stack.