2960x - stack cables connected while switches power on. SFP ports - status unknown

[samokonskiST]

Connected 2960x uplink using SFP ports both stacks and all 4 ports worked good.

Remote tech connected last stack cable between first and last switch, in 2 different 2960x stacks of switches, while switches were  powered on. A longer stack cable was needed.  3 of 4 SFP ports did stopped communicating.

One stack SFP stayed up in switch 2, not master.  Completed reload - other SPF connected in switch 4/0/52

Second stack no connection on either SFP, remote tech power cycled switches.

After power cycle one SFP worked  in Master 1/0/52, other switches SFP ports show "unknown" when inserting SFP.

Configured port 48 on stack with issue and connected second uplink just fine.

Has anyone experienced this with the SFP's?

- GLC-T  P/N 30-1410-03

Looking for documentation on reccommending procedure for connecting stack cables while switches should be powered off or not.

Thanks,

[samokonskiST]

Opened Cisco TAC case.  the following bug was found.

the two different HBRN's below require 2 different IOS and they cannot be in same stack.

 https://tools.cisco.com/bugsearch/bug/CSCur56395

switch#sh ver | s Hardware Board

Hardware Board Revision Number  : 0x05

switch#remote command 2 sh ver | s Hardware Board

Switch : 2 :------------ Hardware Board Revision Number  : 0x05

switch#remote command 3 sh ver | s Hardware Board

Switch : 3 : ------------ Hardware Board Revision Number  : 0x12

switch#remote command 4 sh ver | s Hardware Board

Switch : 4 :------------Hardware Board Revision Number  : 0x12

From Cisco.

Developers have recommended to upgrade the IOS version of switches with a Hardware Board revision Number below 0x10 to the release 15.0(2.0).EX5ES. this is the one attached to this email and should be applied to switch 1 and 2.

For switches with a Hardware Board revision Number above 0x10 to the release 152-2.4.E1ES, which I will send you right away. This should be done on switch 3 and 4.

Now, If you  load the engineering special, you will  need to do a full power-cycle (physically unplug the power and plug it back in for every single switch). A simple ‘reload’ will not resolve this.

The same must be done on Switch-0. For this stack you will only need to load the image attached to this email since all the Hardware Board revision Numbers are lower than 0x10.

done.