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Failover stack (3750-48TS)

Hi, I've stacked 4 3750-48TS together, and configured master member switches.

But what happens when 1 of them fails, and i put a new 3750-48TS into the same location, will the others configure it to the same as the old. And what about the IOS? Will it be upgraded to the same level as the others.


Re: Failover stack (3750-48TS)

No, if you replace a failed member of the stack with a new switch it will not by default take the place of the original member. It will be configured with a different stack number.

However, if a switch fails one of the other members of the stack will become the master and take over the duties of the failed member.

If you want to configure the new switch with the same switch number as the original switch (so that your old port configurations map to the ports on the new switch for example) you can use the "switch X renumber Y" command, where X is the switches current number (e.g. 5) and Y in the switch number of the original switch (e.g. 1).

Before a new switch will become a participating member of the stack you will need to make sure that it is running thr same IOS as the other members. You can do this by physically adding the switch to the stack and then using the "archive copy-sw" command to copy the software from one of the active members to the inactive member.

For more information on the behaviour of the switch stack see "Understanding Switch Stacks" in Managing Switch Stacks at

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