I need to add one new 2960x switch to an existing production stack of 2960x. existing stack has got different IOS than new switch ,but stack protocol version (maj.min) looks the same. do I need to upgrade the IOS or will it work with different IOS if I add to existing stack , please help
System image file is "flash:/c2960x-universalk9-mz.150-2a.EX5.bin"
Switch Ports Model SW Version SW Image
------ ----- ----- ---------- ----------
* 1 52 WS-C2960X-48FPS-L 15.0(2a)EX5 C2960X-UNIVERSALK9-M
2 52 WS-C2960X-48FPS-L 15.0(2a)EX5 C2960X-UNIVERSALK9-M
3 28 WS-C2960X-24PS-L 15.0(2a)EX5 C2960X-UNIVERSALK9-M
Yes, the requirement is to have all the stack members on the same version of IOS code.
You have two choices here: either to downgrade the new member's IOS version to what is running on the stack or to upgrade the stack version and connect the new member.
Take a look at the command: boot auto-copy-sw
...this should copy the current stack image to the newly joining member.
In reality I have never seen this work correctly, so I always configure the new switch with the same images that is running on the stack it is about to join.