07-09-2026 03:58 AM
Hi
we have four 9300L connect as stack, all switch have 17.15.5 IOS XE
when I connect switchs we face high CRC and stack port up/down in switch/s
there is issue in HW or image we use ?
and if it HW
how can port and cable is damage in same time ?
07-09-2026 04:27 AM
CRC means L1 issue, it's probably cable or port issue.
07-09-2026 04:36 AM
Inspect the stacking cable. Is the "Cisco" logo of each end pointing UP or down?
Are the s_crews of the stacking cables finger tight or not?
07-09-2026 04:45 AM
Hi Leo
Yes as I inform you the Cisco Logo up and screws tight
image 17.15.5
boot loader 17.12.x <<- does this need to upgrade also
and we do inspection connect good stack cable into port the issue still same ?
this 9300L so there is no removable Stack adapter
I afraid one of our engineer mistakenly damage the cable and port
your input Mr.Leo
07-09-2026 05:13 AM
@MHM Cisco World wrote:
I afraid one of our engineer mistakenly damage the cable and port
RMA the switch and the cable.
07-09-2026 05:40 AM
did you see same issue before in such port and cable damage ?
07-09-2026 04:54 AM
High CRC on the Stack cable, can you post output of the Below :
show switch stack-ports detail
(most of my observation,. Cable was not intact, could be port issue) - make sure cables are Tight as suggested.
=====️ Preenayamo Vasudevam ️=====
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07-09-2026 05:06 AM
Sure I will attach the output
the cable is tight very good
but as I mention I afraid our engineer by mistake damage the port, can that happened ?
please note that the cisco logo is UP we so so sure about this point before insert stack cable into port
07-09-2026 05:11 AM
but as I mention I afraid our engineer by mistake damage the port, can that happened ?
yes wrong pushing also damage the cables, and board also.
If you get maintenance, turn off whole switch and reseat cables and check one more time , bring back and monitor.
If you have still issue, then RMA.
=====️ Preenayamo Vasudevam ️=====
***** Rate All Helpful Responses *****
07-09-2026 06:36 AM
07-09-2026 06:44 AM
@MHM Cisco World A very basic question, have you tried swapping the stacking cable, or at least tried to identify which one might be defective (assuming the problem is actually the stacking cable)?
07-09-2026 06:54 AM
3rd switch looks like it has an issue. If you clear the counters and they increase quickly, please try the maintenance window and follow the suggestion mentioned earlier. Still, issue TAC and RAM
=====️ Preenayamo Vasudevam ️=====
***** Rate All Helpful Responses *****
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