I have setup a mirror port as I want to analyse in wireshark how a device is communicating for some debugging.

Mirror setup and all showing as mirrored, except the mirror is not actually picking up any traffic from the port I want to watch.

I don't really want to drag an old Cisco switch in just to do this, and I am certain it has worked in the past.

I've set it up a couple of times, and rebooted the switch just in case, no difference.

Are there any traps, have I configured it wrong and has anyone else got it to work or can confirm it does work as intended ?.

Annoying as I need to get some work done.

Thanks for any help