ICX6450 Stacking Question

[jonathan_mchugh]

Hello,

I have 6 ICX 6450 in a stack. 3 on one floor and 3 on another floor. We're no longer leasing 1 of the floors and therefore consolidating everything. The 3 switches that need to be moved are acting as the active and standby switches with all others being members. What would be the best way to move these switches?

Should I make one of the switches NOT being moved the active switch and reload the stack before unplugging those switches to be moved? Or can I just unplug them and move them without doing anything? Not sure what happens to the stack when it loses both active and standby switches.

Any help will be greatly appreciated.

[BenBeck]

I would just make one of the switches that is not moving the master ahead of time by changing the priority:

conf t
stack unit
priority 255

You could also assign a standby in the same way. 

[netwizz]

I would echo what Ben mentioned and also recommend hitless-failover be enabled as well to prevent the whole stack from restarting when you make a topology change.

[jonathan_mchugh]

Thank you guys for the answers I really appreciate that.

So I could do
 
conf t
hitless-failover enable

Then run
conf t
stack unit
priority 255

Then the stack doesn't have to be restarted? Would the current master switch restart after assigning a new master?

[netwizz]

That I am not sure.  I would have to do a lab test to be sure, but at the moment I am hammered making firewall changes for another project.

Certainly, if you remove switches that are NOT the master or standby hitless-failover should allow just the moved switches to restart.

That said, I do not know if it will be a simple re-election for a master change or if that will result in a stack reload.  You would probably need three (3) or four (4) of those to build a stack and test.

From the sounds of it, you may need to do some stacking gymnastics and musical switches in that the definition merely says:

Hitless stacking failover provides automatic failover from the active controller to the standby controller without resetting any of the units in the stack and with sub-second or no packet loss to hitless stacking-supported services and protocols.


That would lead me to think you would have to do some numbering, so a desirable standby is elected first THEN failover from the active controller to that standby... and then change to another standby and wait for the re-election to finish.

***

This is the kind of stuff where I just build a lab or schedule downtime if I cannot be bothered.  It is also the type of stuff I do not guarantee will not cause an outage to management.