Loopback Test for Stacking Ports

[LJ Gabrillo]

Hi everyone,


Just curious, 
Is there a way to loopback test the stacking port on a switch
e.g., I will connect the stacking cable to port1 and port2 of the switch e.g., "shorting it" creating a "loop"

Once done, I will execute <this command> to test if the ports are okay as well as the cable


Is there a way Cisco can do this?
e.g., 

[Zach S]

LJ,

I don't believe a stack port loopback is possible. It's a physical interconnect that more or less lets multiple asics communicate, but the asic(s) on a single switch already share common backplane.

If you want to get the status of your stack ports you can run "show platform stack-manager all", I pulled that command from a 3750, other models may use different syntax.
 

Here's a link if you want to dig more into stacking technology:
http://www.cisco.com/c/en/us/products/collateral/switches/catalyst-3750-series-switches/prod_white_paper09186a00801b096a.html

[LJ Gabrillo]

Hi Zach, 

Actually there is one, 
After researching there is one way to loopback test the device
SEE LINK

Anyway, in summary, we loop the stack ports, reboot the switch and wait for a message
If a message goes

SM: Detected stack cables at PORT1 PORT2

There your ports are okay

[Zach S]

LJ,

I stand corrected, thanks for the info.

[LJ Gabrillo]

haha yeah, after I posted this question and did some deep research e.g., reading every letter of the guide, i stumbled upon this one

Thank's for the reply though, appreciate the input