SPANTREE SWITCH IOS Upgrade

[r.kate]

Hi ,

I have three switches connected to each other through fibre . One of the switches which is in client mode needs to bre reloaded with some new IOS . I have been told there will be a network outage for one minute while all the other switches configure themselves for Spanning tree . Please can anyone shed some light on it .Cant understand why would a IOS upgrade on one switch bring the whole network down .

Thanks

raj

[Prashanth Krishnappa]

When you say the switch is in client mode, what do you mean by it? Is it VTP client?

If the switch you are upgrading is not the STP root, the outage should be nil to minimal(there will be some flooding when the link between the switches goes down and up since it generates a STP TCN).

If it is the STP root, another switch in the network will have to be elected as the root and will involve recalculation.