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3750X Stacking version

I have simple stack of a 3750X-24T-S and 3750X-24S-S running c3750e-ipbasek9-mz.122-58.SE2.bin. IPBase Licenses are Permanent and Active on both switches.

They will not stack as they are running different stack versions. The "sh platform stack manager all" command shows the 24T-S Stack State Machine View as version 1.46. The same command for the 24S-S Stack State Machine View as version 6.46.

Just received both switches this week. How do I get them to the same stack version so I can form a stack?

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VIP Super Bronze

Usually when switches will

Usually when switches will not stack, it means the IOS is different between them.

Can you post "sh ver" from both devices:

Major Version Number Incompatibility Among Switches

Switches with different major Cisco IOS software versions usually have different stack protocol versions. Switches with different major version numbers are incompatible and cannot exist in the same switch stack.

Minor Version Number Incompatibility Among Switches

Switches with the same major version number but with a different minor version number are considered partially compatible. When connected to a switch stack, a partially compatible switch enters version-mismatch (VM) mode and cannot join the stack as a fully functioning member. The software detects the mismatched software and tries to upgrade (or downgrade) the switch in VM mode with the switch stack image or with a tar file image from the switch stack flash memory. The software uses the automatic upgrade (auto-upgrade) and the automatic advise (auto-advise) features. For more information, see the "Understanding Auto-Upgrade and Auto-Advise" section.

To see if there are switches in VM mode, use the show switch user EXEC command. The port LEDs on switches in VM mode stay off. Pressing the Mode button does not change the LED mode.

You can use the boot auto-download-sw global configuration command to specify a URL pathname for the master switch to use to get an image in case of version mismatch.


New Member

Did you ever discover a way

Did you ever discover a way to get your stack software versions to be the same?  I've got the same problem, both are 24s-s switches running the same IOS version, but one has stack version 1.46 and the other 6.46.

New Member

How did you load the IOS?   I

How did you load the IOS?   I use the archive command with tar files and the stack version seems upgrade or downgrade with the ios. 

New Member

Did you ever fix this ? I

Did you ever fix this ? I have the same issue on a 2960x stack - 1.56 and 7.56 when upgrading to with 15.2(2)E5 from 15.0(2)EX3.

But this is on one stack out of nine - the other 8 are fine.



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As mentioned by Reza, stacking versions might differ between different versions of the IOS, so insure all stack members are using the same IOS version and the stacking version should match.

New Member

Hi Joseph,

Hi Joseph,

Thanks for your quick response, we're upgrade a stack of two both running 15.0(2)EX3 and using the archive command upgraded to 15.2(2)E5 - we did this on 9 stacks, with just this stack experiencing the problem.

The other 8 stacks all report 1.56 on both switches, it's this one reporting 1.56 and 7.56.

When we rolled back to the previous version both switches worked and both reported 1.55.


EDITED to add - all switches are the same model - WS-C2960X-48FPS-L

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