3750x versions

[Bob Greer]

Hi there,

Thanks for reading!

I need add switches to an existing stack.  All hardware is 3750x but the versions are different.  The versioning on the bench switches is
(C3750-IPSERVICESK9-M), Version 15.0(2)SE6, RELEASE SOFTWARE (fc2)
BOOTLDR: C3750 Boot Loader (C3750-HBOOT-M) Version 12.2(44)SE5, RELEASE SOFTWARE (fc1)

The production switch versioning is

(C3750-IPSERVICESK9-M), Version 12.2(55)SE9, RELEASE SOFTWARE (fc1)
BOOTLDR: C3750 Boot Loader (C3750-HBOOT-M) Version 12.2(44)SE5, RELEASE SOFTWARE (fc1)

Are these compatible to stack as they are currently versioned?

Thanks again for reading!

Bob

[luis_cordova · Accepted solution]

Hi @Bob Greer,

I found this in this link:

Software Compatibility

Software compatibility between the stack members is determined by the Stack Protocol Version number. To view the stack protocol version of your switch stack, you can issue the show platform stack manager all command.

Switches with the same Cisco IOS software version have the same stack protocol version. Such switches are fully compatible, and all features function properly across the switch stack. Switches with the same Cisco IOS software version as the stack master immediately join the switch stack.

If an incompatibility exists, the fully functional stack members generate a system message that describes the cause of the incompatibility on the specific stack members. The stack master sends the message to all stack members.

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

https://www.cisco.com/c/en/us/support/docs/switches/catalyst-3750-series-switches/71925-cat3750-create-switch-stks.html

Regards

[Francesco Molino · Accepted solution]

Hi

You need to downgrade the new switches to same version as the production switches or upgrade the production first to same version as new ones.

If you have the auto-upgrade command into your production stack, by stacking the new switches they'll be downgraded to IOS running on production.