Stack 1 Backup/Stack 2 Master Flip-Flop

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So last night we had stack 1 of our 3 switch stack go down due to a UPS problem.  Fail-over occurred perfectly and stack 2 became the master.  Once we fixed the UPS, the stack 1 switch came back up without a problem.  Now stack 2 is the master and stack 1 is the backup.  What is the easiest and safest way to get stack 1 back as the master and stack 2 back as the backup?

Thanks for your time and answers,
Stan
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Stanley Riley Jr.

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Posted 3 years ago

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Colatuno, Joe, Escalation Support Engineer

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Hey Stan,

is the 3rd node in the stack a standby?  Is it master capable?  If not master capable, you can just reboot slot 2 and slot 1 will regain mastership.
(Edited)
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Stanley Riley Jr.

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Hey Joe, thanks for your quick reply!

The 3rd node is not master capable.

Do I need to power cycle the device, or can I just do the command 'reboot slot 2'?
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Patrick Voss, Employee

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You can use the command "run failover" but it will reboot the current master (essentially the same thing Joe mentioned. The stack will work fine the way it is and you will not have to cause any network disruption. As Joe mentioned as long as the 3rd slot is not master capable (this can be checked with the "show stacking configuration" command") the first slot will take over as master.
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Patrick Voss, Employee

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Hi Stan,

"run failover", uplugging the switch or the command "reboot slot 2" will all do the same thing.
(Edited)
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Stanley Riley Jr.

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Patrick,

Awesome!  Thanks for your help guys.

Stan
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Stephen Williams, Employee

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