fcs error on link

Hardware MikroTik hardware general
1

I have an ongoing issue with my CCR1009-7G-1C-1S+, where I get the fcs error on the link to my AF24. I have replaced to cable, connectors, POE and Ethernet patch cables. I also changed from ether1 to ether7. None of this fixed it so I replaced to AF24. The issue is still there and it is killing the download speeds. We have tested the cables and they have never shown any errors. It is linked at 1000Mbps full duplex. I tried flow control on, off and auto.
Has anyone else found a fix for this issue? It almost seems like a compatibility issue with UBNT and MT.

Firmware is 6.42.7

2

Have you looked at grounding of the devices or do you have any inline surge arresters ?

I’ve had my fun with MTK devices and grounding before causing massive link flaps and corresponding fcs/Rx Align Errors.

For shits and giggles have you tried to put an intermediary device like a 8 port gigabit switch inbetween the two to see if this cures the issue ?

3

If you check both Mikrotik and Ubiquiti forums, you will find a lot of threads about this topic.
For me, the issue was with the AF24 that hadn’t the clean line of sight and the wireless frame errors were translated to FCS errors on the ethernet too. Fixing the wireless link, solved the issue.

4

Both the POE and CCR are plugged into the same power outlet so they have the same ground source. How would you suggest I expand on the grounding? It seems like adding an unmanaged switch would isolate the ground.