Automatically Adding or Replacing Nodes in a Stack

You can easily automatically add or replace nodes in an existing stack.



You can only replace a switch with the same switch model, or with a model from the same switch series (family) with the same number of ports, but a different port type. For example, you can replace an ExtremeSwitching X450-G2-24t-10GE4 with an ExtremeSwitching X450-G2-24p-10GE4 (24t → 24p).
Connecting a new node to a stack automatically triggers the following tasks in a stack:
To start automatic node replacement:
  1. Prepare the replacement node:
    1. If the replacement switch is not out of the shipping box, remove any configuration and restore the factory defaults by running the command unconfigure switch {all | erase [all | nvram]} with the all option.
    2. If the replacement switch is going to be the backup node, check for feature license mismatches between it and the master by running show licenses {[slot slot |all]} {detail} on both switches. Install licenses as needed to the replacement node by running the command enable license {software} [key ] or;

      install license file filename for universal platforms.

    3. Power down the replacement switch.
  2. Remove the current node from the stack.
  3. If you are changing to a different port type (for example, 24t → 24p):
    1. On the master, run the command configure slot slot module module_type , and change the module_type as applicable.
    2. Save the configuration (save configuration {primary | secondary | existing-config | new-config} ).
  4. Physically connect the new switch to the stack, and power it up. For information about cabling, see the hardware installation guide for your switch.
  5. Configure the switch port and speed for stack communication on the connected port of the new node for ExtremeSwitching X465, X590, X620, X695 series switches by running the command configure stacking-support stack-port [stack-ports | all] selection [native {V40 | V80 | V160 | V200 | V320 | V400 {alternative-configuration | help}} | alternate].
    For ExtremeSwitching X460-G2, X450-G2, X440-G2 series switches, the auto-discovery feature automatically turns on stacking support for the connected port.
    Platform Stacking Mode Supported Ports Stacking Method Port Speed
    X460-G2 Native VIM-2Q V160 40G
    VIM-2SS 10G
    Alternate VIM-2X 10G
    Front panel 10G
    X440-G2 Alternate Front/rear panel 10G
    X450-G2 Alternate Front panel - 10G


    The auto-discovery feature takes between 5 and 10 minutes to complete. During this time, the new node is rebooted twice, and if an image upgrade is required, it is rebooted a third time.

    To determine that the auto-discovery feature has finished adding the node to the stack, on the master run the command show slot {slot {detail} | detail } without the detail options. When auto-discovery is finished, the slot appears in the output as "Operational". If the node appears as "Failed", run the command show slot {slot {detail} | detail }, specifying the slot and using the detail option to see why the node has failed to join the stack. The most likely problem is that there is a feature license mismatch. To resolve this, re-run the procedure ensuring that you complete Step 1b.


    Auto-discovery is enabled by default. To turn on or off auto-discovery, use the following command: configure stacking-support auto-discovery [disable | enable].

To manually add or replace a node, see Manually Adding Nodes to a Stack.