c9300 switch stacking failures

[bryantsteve]

Attempting to stack (4) c9300 48 port E licensed IOSXE 16.6.6, licenses and codes match up, provisioned the switches and configured the switch priorities on desired Master and switches in the stack, We keep encountering failed port connections and boot up looping, have tried various combinations of stack cable swaps and cabling configurations as well as timing power up sequences, nothing works, has anyone encountered issues/have suggestions to get these switches to stack?  

[balaji.bandi]

can you post the console logs, please?

is the PSU are same ?

[bryantsteve]

Hi Balaji



PSU I assume means power supply unit, yes these are all the same



The gist of the console logging is

Stack Cable authentication failed for cable inserted on Stackport2 on switch 1 (as I connect stack cable to switch 2



Reloading chassis because cable auth failed on stackport



Process Manager is exiting reloaded fp action required following by report that crashinfo zip file has been generated



At this point the switch goes into a boot up loop which can only be interrupted by disconnecting the stack cable from switch 2 , switch sometimes fully loads the IOS but most of time it goes into rommon, at that point I can only recover by command boot bootflash:

[balaji.bandi]

Looks like some Bug  CSCvo12056

Workaround:
RMA the cable which is failing

[paul driver]

Hello

can you post the following :

show switch detail

dir flash:

show boot

show switch stack-ring

[bryantsteve]

I went thru a box of 25 or 30 stack cables and found 5 that worked and the 4 switch stack is working. I suppose CSCvo12056 Bug fix of RMA'ing cables is spot on

[balaji.bandi]

Glad here that that lot of cables were the same batch.

hope you the solutions resolved now.