Mimosa B24 eth port flapping

I have a problem with Mimosa B24 and Mikrotik hEX S … Sometimes I see link down and up in log. I try new UTP (cat 5E with shield, 6), upgrade FW, new POE but problem still persist. Now I connect switch between router and mimosa - everything seems OK.

Could be a bad cable, how long is it and how long is the cable between the router and the B24?

What was the model of switch that you put between the router and the B24?

What is in the logs on the B24 and the Router at the time of the port flapping?

I have a problem on three B24 … cable long between 5 - 10 meters. Model of switch is TP-LINK TL-SG108.

When the problem occurs. In log I see:
2019-08-22 19:20:19 (UTC +0000) root: MIMO_EVENT ethernet link down
2019-08-22 19:20:23 (UTC +0000) root: MIMO_EVENT ethernet link up (1000/Full)

On first PTP problem occurs three times peer day … on second link 20-30 times peer minute

Does the router show the link going down at the same time?

Yes, link going down at the same time.

How long does the link go down for? What do you have to do (if anything) to bring it back up?

Link go down and up take about two second. After link down and up connection restore automaticaly.

Have you tried turning off Auto Negotiation on both the router and the B24 and hard setting it to 1 Gig?

Yes, I set both side hard to 1Gbit or 100Mbit but problem persist.

What version of firmware are you running on each device?

Im use lasted version on all devices…

You running latests beta, stable or long term? What is the actual firmware version on each device?

All devices have 2.5.2-PTP

and the Mikrotik Router?

On Mikrotik router Im using 6.43.4 or 6.45.5

6.43.4 is older then the current firmware for the long term channel, I would upgrade it because there were several security vulnerabilities fixed after 6.43.

How are you powering your B24? Obviously it’s not loosing power, are you using the supplied PoE adapter or another brand? When you switched PoE injectors did you change brands? What about the cable between the router and the PoE injector, has that been checked/replaced?

I see this problem firstly on 6.43.4 version, but now I using 6.45.5

B24 is power by original POE adapter, I try to change it, but problem persist. All UTP and RJ45 I try change too.

What did you change the PoE Injector to? Another Mimosa PoE Injector or some other brand?

We have the same problem. I change everything from Cat6 UTP cable and POE injector as well

Standard Mimosa feature. No extra charge for the ulcer they are giving you.

Using Cat6 Factory made cables is always Mimosa’s go to excuse but I’ve spent a small fortune on Factory cables that came with Metered reports on each one of them and they make no difference.

You could try installing a Netonix switch and powering the Mimosa from it. Make sure there are no surge Ethernet arresters in the path. That works sometimes

If port keeps flapping I’ve had some success with setting the Mimosa Ethernet port to Preferred Slave and hard coding the Netonix to Gig. This breaks the RFC for Gig which MUST autoneg and it doesn’t work often or for very long though before you just give up.

The pathetically poor quality of the Mimosa’s Ethernet port hardware is the reason that I am removing them all (I had about 30 B5’s at one time) from my network as quickly as they flap - which is pretty fast.