SG200-50P Port Mirroring Not Working

[JustinR27]

Hi,

I've been trying to setup port mirroring to monitor traffic on a port that is experiencing thousands of packet errors to no avail. I've setup the port experiencing the packet errors as the source interface, and the port I want to use to run a packet capture as my destination interface but the status just says "Not Ready" and no traffic is being mirrored.

Does anyone have any advice on what might be wrong?

[Flavio Miranda]

Did you follow any guide? If does not, then try this:

https://www.cisco.com/c/en/us/support/docs/smb/switches/cisco-small-business-200-series-managed-switches/smb77-port-and-vlan-mirroring-on-the-200-300-series-managed-switch.html 

[JustinR27]

Yes, that is the exact guide I followed.

[Flavio Miranda]

Which is your version? This guide mention 1.3.0.62.  Should not be this but, just in case.

[JustinR27]

I am on version 1.4.2.4

[JustinR27]

Some additional information in case it's helpful. The port experiencing the issues is part of a LAG and is connected to another switch. It's the only port in the LAG that is getting packet errors. I already tested the cable with a cable tester so I know it's not a bad cable.

[Flavio Miranda]

Maybe that´s the reason.  Can you try with a different port just to make sure it works?

[JustinR27]

So I switched it to a different port that is not part of a LAG and can confirm it's working. The Port Mirror status is "Active" and I can see the traffic in wireshark. When I switch it back to the port that was experiencing errors, it goes back to "Not Ready". Is it not possible to mirror a port if it's part of a LAG?

[Flavio Miranda]

Sounds like the problem you are seing on this port may cause the Port Mirroring  problem. 

Using Web interface I am not sure if possible, but on the CLI I´d recommend to re-configure  this port with the command "default interface"

  Or you may use a different port instead.

[JustinR27]

Unfortunately the SG200 series switches don't support SSH for management so no CLI.