WS-12-250-AC Port losing link

[valnet]

Greetings,

I've deployed a WS-12-250-AC at a site which has two FM stations on site. The electronics for the FM sites indicates they are fairly low power, with the forward power indicators on the drivers reading 250W and 500W.

Our previous installation at the site has a PMP100 cluster, CMM3, AF5x, and RB2011 router. We had no issues with loss of Ethernet link on those devices.

This installation updates our equipment to an RB1100AHx2, Netonix WS-12-250-AC, ePMP 1000 cluster, CMM3, and PMP100 cluster, with the same AF5x backhaul. We also reinstalled with better grounding connectivity and a wall rack.

Site Image

All cables are shielded except the yellow one. Which is both temporary, and not exhibiting any problems.

The grey cables are shielded CAT5e manufactured cables.

The grey cable indicated is losing link about twice a day; usually close together in time - today it was 5:17am and 5:24am. Each time is long enough to trip an outage alarm (~5 minutes).

Logs show the port flapping during that time. The Netonix interface shows an error counter under Tx Drops, currently 39 errors after being cleared yesterday afternoon. At that time, it was about 1750 errors.

Any suggestions as to why this port might be losing link? It's happened a half dozen times now, so it is definitely not an isolated incident.

[valnet]

This same WS-12-250-AC is also having trouble on port 5, but it may or may not be related. Port 5 shows 7160 errors, and will occasionally stop communicating with the AP on the tower.

[sirhc]

Well to find out if it is a bad switch port simply swap the cable that is having issues with a port that is not having issues.

If the problem follows the cable you have eliminated the switch and can now move on to what is the real problem.

[valnet]

It seems unlikely that there's a bad switch or cable - it was working correctly for about six or seven weeks before the problem started occurring; though that cable is a little taunt. Not stretched hard, but definitely taunt.

[sirhc]

I also hope you do NOT have any port speed/duplex set to anything other than AUTO on both switch and device especially at an FM site.

My guess is this is not a switch issue but a cabling issue or FM noise on the cable.
I do hope you also have the tower and tower ground rods bonded to the electrical service ground rods with a heavy wire like #2 Green else you will have a ton of ground current on the cables which can damage equipment and interfere with communications.

[sirhc]

Stretching or kinking an Ethernet cable during installation will definitely trash it as the pairs are wound to a specific tolerance to eliminate cross talk between pairs.