Cisco 3750 Switch Stack

[Ranil Herath]

Hi All,

Just wanted to know what would happen when a stack member is disconnected from the stack, for example to due to a stack cable failure.

Lets say the stack has 3 members and the switch 3 (not a master) disconnected from the rest of the stack. I'm guessing this will split the network into two and each segment will be able to communicate with devices on that segment. What will happen to a server that's on an LACP trunk connecting to switch 2 and switch 3? Will the entire stack reboot once switch 3 is reconnected to the stack?

Appreciate your help

Many Thanks

Ranil

[Joseph W. Doherty]

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Posting

If the stack is dual connected, as it should be, the remaining stack members won't segment and will continue to function.  Your port-channel will continue to function.

If the switch is re-added to the stack, it will just rejoin the stack.

[Ranil Herath]

Thanks Joseph.

The stack is dual connected. I was thinking of a situation where both stackwise cables failing on a switch.

[Joseph W. Doherty · Accepted solution]

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

(Hopefully) that's unlikely, but if it happens (or you didn't have dual connections to begin with), stack will segment.  Each segmented stack will believe its the stack.  Impact would be "messy" as you would have two "duplicate" devices on the network.

[Ranil Herath]

Thank you very much Joseph!

Appreciate your help