topic Re: adding a switch to a live stack with different HW Version? in Switching

adding a switch to a live stack with different HW Version?

AntMan75 — Thu, 19 Jun 2025 13:25:21 GMT

Hi All,

Hope you can help. I currently have a 2 switch stack (C9200L-24P) I need to add a switch and have the same model switch which I have changed the SW version to match (17.6.5) but have noticed the new switch is HW Version 06 while the stack switches are HW Version 03. Will this cause a problem when I connect the new switch and is there a solution?

Thanks in Advance

Re: adding a switch to a live stack with different HW Version?

Enes Simnica — Thu, 19 Jun 2025 13:59:15 GMT

hello G.

Matching the software version (17.6.5) was the right first step. While Cisco doesn't officially support mixing HW versions 03 and 06, it might work, and for sure / I've seen similar setups function with minor quirks.

Before fully adding it, I would suggest to do these steps: 1. Set the new switch to low priority (like "switch 3 priority 1/"). 2. Temporarily connect it and monitor logs for errors. 3. Watch "show stack-ring activity" closely......

ANd then/, If u notice issues, u may need to either find a matching HW v03 switch or upgrade the whole stack to a newer IOS that better supports both versions.

hope it helps G...

-Enes

Re: adding a switch to a live stack with different HW Version?

MHM Cisco World — Thu, 19 Jun 2025 14:05:42 GMT

the different ver. will not join
stack need same ver. run in all SW

MHM

Re: adding a switch to a live stack with different HW Version?

Torbjørn — Fri, 20 Jun 2025 07:04:32 GMT

Hello @AntMan75,

As long as all stack members are C9200L-24P it should not be an issue.

Re: adding a switch to a live stack with different HW Version?

Leo Laohoo — Fri, 20 Jun 2025 07:11:43 GMT

software auto-upgrade enable

The command above is the most relevant.

If this command is present, any switch members with the incompatible software will be able to join the stack. The new switch member's software will get upgraded to be the same with the entire stack.

Re: adding a switch to a live stack with different HW Version?

AntMan75 — Fri, 20 Jun 2025 07:35:33 GMT

Hi All

Thanks for the quick responses. My next maintenance window is next week so I'll let you know what I find

Regards

Re: adding a switch to a live stack with different HW Version?

wajidhassan — Fri, 20 Jun 2025 10:22:02 GMT

Hi there,

Cisco usually ensures that different hardware versions within the same switch model are compatible, especially when they’re running the same software. The newer hardware version likely just includes internal improvements or updated components, but it’s still fully stackable with older versions.

Re: adding a switch to a live stack with different HW Version?

AntMan75 — Thu, 10 Jul 2025 10:49:23 GMT

Hi All,

Thank you for your help. Once I made sure I had the correct switch number, licenses and priority on the new switch it added to the stack with no issues. The differing hardware version made no impact. Again the replies were much appriciated.