Unable to add 2960X to Stack. Stack Ports Showing Down

[martinezaw]

Hello, I'm REALLY baffled at why a 2960X is not being added to our stack. I matched the new member's IOS to what the stack had. The sdm prefer settings match. The licenses both show lanbase. Yet, both the stack and and the new member show stack ports as down.

The funny thing is that when I plug the cable between the new member's own two stack ports. They show up but as soon as I connected it to the stack they go down. 

The stack has two members. I am trying to add a third.

On start up, the new member shows this... but then the stack ports go down...

Front-end Microcode IMG MGR: Installed 3 image(s) in cache:

Front-end Microcode IMG MGR: found microcode images for 3 devices.

Image for front-end 0: flash:/front_end_ucode_cache/ucode.0

Image for front-end 7: flash:/front_end_ucode_cache/ucode.0

Image for front-end 14: flash:/front_end_ucode_cache/ucode.0

Front-end Microcode IMG MGR: Preparing to program device microcode...

Front-end Microcode IMG MGR: Preparing to program device[0]...27542 bytes.

Front-end Microcode IMG MGR: Programming device 0...rwRr

% Front-end Microcode IMG MGR: address 0, unable to switch to boot loader mode.

% Front-end Microcode IMG MGR: unable to program device: 0

% Front-end Microcode IMG MGR: malformed microcode cache

SM: Detected stack cables at PORT1 (only one cable was plugged in here but when I have both cables plugged in it shows detected at PORT1 and PORT2)

Waiting for Stack Master Election...

SM: Waiting for other switches in stack to boot...

Any ideas????

The new member never sees anyone and so becomes master.

[Reza Sharifi]

Try to provision the new member and than add it:

switch 3 provision <the new member>

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960x/software/15-0_2_EX/stack_manager/configuration_guide/b_stck_152ex_2960-x_cg/b_stck_152ex_2960-x_cg_chapter_010.html#task_1177470

HTH

[martinezaw]

What concerns me is the boot message below... The switch boots up seemingly normal but displays the below...

Front-end Microcode IMG MGR: Preparing to program device microcode...

Front-end Microcode IMG MGR: Preparing to program device[0]...27542 bytes.

Front-end Microcode IMG MGR: Programming device 0...rwRr

% Front-end Microcode IMG MGR: address 0, unable to switch to boot loader mode.

% Front-end Microcode IMG MGR: unable to program device: 0

% Front-end Microcode IMG MGR: malformed microcode cache

This makes me wonder if there is some sort of software issue affecting the switch.

[martinezaw]

I have even swapped the switch out with another one. (Using same stack module). When I plug the cable from stack 1 to stack 2 on the same module... the switch can see the stack ports as up. When I plug the module/stack cable into module of the other switches, the stack ports change to down.

It's reasonable to assume it is not the module or cable since the ports come up when plugged into same switch?

The added switch also has same IOS version and features (lan-base)

Anyone have *ANY* ideas???

[martinezaw · Accepted solution]

I figured it out for anyone else who may encounter a similar thing...

The stack's stack port speed was set to 10Gb (have no idea who did it or why) not the default 20Gb. The switch I was adding was defaulted to the normal 20Gb. I had to set the stack port speed on the new switch to 10Gb to match the stack and then it worked. 

You would think a speed mismatch would show up in the logs, but it does not. Just FYI.

[mpititto]

Thank'you very mouch, the problem is resolved.