2960 Mixed Stack IOS upgrade

[jvooght01]

I am working with several mixed stack 2960 series switches consisting of 2960S and 2960X switches stacked together.

Current recommended versions are not the same for those switches (See below), can those disparate versions live together on the individual switches in the same stack, and not cause issues?

2960X Recommended: c2960x-universalk9-mz.152-7.E2.bin

2960S Recommended: c2960s-universalk9-mz.152-2.E9.bin

[balaji.bandi]

I do not believe you can have different versions on the same stack.i have worked on 2960 long ago. you can choose one of them compatible for both and upgrade.

[Leo Laohoo]

Not going to work.
Might as well split the stack into two.

[Martin L]

no, your stack will run on 1 single IOS; you can have different IOS stored in flash -if there is room - but stack runs on main ios.

in case of 2960s, I was not aware you can mix S with X models;  do you have some issues/problems?

Regards, ML
**Please Rate All Helpful Responses **

[Matt86]

Hello Martin,

Yes there is a problem with PACL unloading on S models due to higher cache on X models.

When high number of 801.x connection occur, this fill the S's cache that cannot apply the PACL (from ISE) anymore.

A syslog msg is trigger = 

%ACLMGR-4-UNLOADING: Unloading PACL input label X Gix/x/x IP feature (hostname)

For now, I just reload the impacted slot as a workaround with an EEM

Rgds, 

Matt