I've noticed that with no other traffic on the system I am registering a constant 97kbps/124 packets per second both RX and TX on a point-to-point backhaul link, ie the tx/rx readings at both ends are identical. See image.

At each end is an RB532 with nstream and polling on. No interface upstream or downstream of the link is carrying this traffic, which is just between the two wlans interfaces.

Any ideas, or suggestions for further investigation?

Torch the link and see if any traffic is passing through it.

Cheers

Stumbled quite serendipitously over the answer - pretty rare series of events, I admit, but I'll confess all here in the hope it might help someone in the future.

Was setting up a new server at the Gateway with Ubuntu Server, administering it remotely with Webmin. For some reason using Webmin's command-prompt function to try to ping other machines on the network didn't trigger the shell responses - all I got was a blank page - so I moved on. However the 'pings' had been triggered and were still running - endlessly without my being aware of it.

> sudo killall ping put a stop to it, but it was a warning against using ping without a -c [count] value, yes?