Using the Mode Button to Automatically Stack

The mode button is a front-panel button used to select alternate front-panel LED display modes that convey additional port and stacking information. On all ExtremeSwitching Universal platforms, this button can be used to initiate automatic stacking.

Automatic stacking using the mode button feature is aimed at zero-touch customers who want to deploy stacking in remote sites. You can ship switches to remote sites and have a local (non-technical) installer mount the switches in the rack, attach the power cables, and connect the stacking cables. The installer can then press the Mode button to initiate the automatic stacking sequence. After stacking is complete, the switches can be provisioned and managed remotely using a cloud connection.

You can stack 1 to 8 nodes. If you have only a single node in the stack, stacking occurs in a daisy-chain topology. If there is more than a single node in the stack topology, the stack is connected as a ring. If a ring is not detected, the automatic stacking sequence does not run when you presses the Mode button.

You can build a stack a node at a time by initiating automatic stacking on one switch that, after rebooting, becomes the primary node. Attaching nodes subsequently causes those nodes to join the stack.

Important

To use automatic stacking, each switch must have the factory default configuration. If any of the switches do not have the factory configuration (directly 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.

License level and ExtremeXOS version mismatches are automatically reconciled. However, license mismatches due to installing feature licenses cannot be resolved automatically. The applicable node is left in the failed state.

To use automatic stacking, all switches must:

Have the same license level.
Be running ExtremeXOS 30.3 or later.
If the primary node is running a newer version of ExtremeXOS than the nodes, the nodes are upgraded to the newer ExtremeXOS version.
Not have an Extended Edge Switching topology.

Note

A mixed stack of ExtremeSwitching 5720 and 5520 switches cannot use automatic stacking.

To begin automatic stacking:

Remove the switches from their boxes and mount the desired number of switches in the desired locations. For information about physically setting up switches, see ExtremeSwitching Quick Reference Guide for the switch series.
Attach the stacking cables to form a ring between the switches (see Ring Topology: Recommended for Stacking).
Attach the power cables to each switch, and then plug them into a power source.
Wait for all switches to boot (approximately 2 minutes).
Verify that there is LINK UP on all stack ports by checking the stack port LEDs.

Note
A single node stack (no cabling) will not have a lit LED.
On the switch that is going to be the stack primary, push the Mode button twice and verify that the STK LED is solid green.
Press and hold the Mode button for at least 5 seconds.

AFter releasing the Mode button (following the final step), the front panel port LEDs (on the primary node) flash in an alternating pattern followed by a delayed reboot of all of the switches. The LEDs flash for approximately 15 seconds prior to reboot. After the reboot completes, the switches are stacked.

If the front panel port LEDs on the primary node do not flash (flashing LEDs indicate that automatic stacking has been initiated), try the following:

Check the cabling for correct ring topology, and fix as needed (see Ring Topology: Recommended for Stacking).
Check that the stack port LINK UP LEDs are lit (see step 5).
Note
A single node stack (no cabling) will not have a lit LED.

If you can verify that both the cabling and the LINK UP LEDs are lit, then further troubleshooting requires accessing the switch with a console or by cloud access to check the switch's error log.