Automatically Adding or Replacing Nodes in a Stack

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

Important

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:

Adds New Nodes—When a new switch is connected to a stack, the switch is automatically:
1. Configured with the proper stacking support parameters needed to bring up either native or alternate stack ports. This automatic configuration (auto-discovery) is supported on ExtremeSwitching X440-G2, X450-G2, and X460-G2 series switches. Switches other than the ones listed above require that you configure stacking support on the stacking ports manually.
2. Assigned the lowest available slot number.
3. Set as stacking master-capability if the stack has only one master-capable switch (the master itself) and the switch is directly connected to the current stack master. Otherwise, the new switch is not made master-capable.
4. Assigned the stack MAC address.
5. Rebooted, which then causes the new node to join the stack.
Incompatible ExtremeXOS Check—Checks for and resolves incompatible ExtremeXOS software versions of stack nodes. If the new switch is running an incompatible version, the version is reconciled by running the synchronize {slot slotid} command for that switch causing the new switch to align with the stack master.
Note
You cannot automatically update a switch running ExtremeXOS 30.2 or earlier to ExtremeXOS 30.3 or later due to a file system compatibility issue. If a switch has ExtremeXOS 30.2 or earlier, prior to inserting the switch into the stack topology, you need to manually upgrade the switch (see Upgrading the Software on all Active Nodes).
License Mismatch Check—Checks for and resolves software license mismatches between all master-capable nodes. The following command is issued: configure stacking {node-address node-address | slot slot-number} license-level [core | advanced-edge | edge].
Note
License mismatches due to installing feature licenses cannot be resolved automatically. The node is left in the failed state.

To start automatic node replacement:

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 | all] on both switches. Install licenses as needed to the replacement node by running the command enable license {software} [key ] .
3. Power down the replacement switch.
Remove the current node from the stack.
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} ).
Physically connect the new switch to the stack, and power it up. For information about cabling, see ExtremeSwitching and Summit Switches: Hardware Installation Guide for Switches Using ExtremeXOS Version 30.7 .

Configure the switch port and speed for stack communication on the connected port of the new node for ExtremeSwitching X670-G2, X465, X590, X620, X690, X695, and X870 series switches by running the command configure stacking-support stack-port [stack-ports | all] selection [native {V160} | V320 |V400 {alternative-configuration} | help} | alternate].

For ExtremeSwitching X460-G2, X450-G2, and 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
	Native	VIM-2SS	–	10G
	Alternate	VIM-2X	–	10G
	Alternate	Front panel	–	10G
X440-G2	Alternate	Front/rear panel	–	10G
X450-G2	Alternate	Front panel	-	10G

Important

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.

Note

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.