I am running a backhaul link using a 911G direct connect via a cable and POE adapter to a RB750GL. This will randomly stop transmitting data on the LAN. I have tried changing POE adapters, the 911G, the 750GL, and forcing the port to 100 Full duplex. It will come up and work for a period of time (somtimes a day or two) and then just quit. Once it quits, it may pick back up and work again for a minute or two at a time but tends to never fully recover. It also will not negotiate gigabit speed on the LAN at any time. I haven't yet tried changing the cable on the tower but I guess that will be the next step since I have seemed to exhaust all other things I can think of.

This same setup was being used before on this same cable running for a few months but using a RB711UA-5HnD.

Any help would be appreciated.

How long is that cable? Have you tested it?

The cable is less than 100 feet. It was a working setup before changing to a 911G.

So I can verify completely that it's not on the RF side of the link that I'm losing my connection. Is there any problems with the LAN on the 911 boards? I mean this link is mikrotik to mikrotik direct connected. I've replaced everything and it's still happening.

Now I have replaced the cable as well. I am still getting random drops on the LAN interface of the 911 to 750. They are fewer than they used to be but still there.

Can you not use a POE on the gigabit interfaces to power the 911 boards or something?

Does anyone have any ideas. All equipment changed out and still issues. This has to be a software bug since it was working fine until I switched to a 911 board.

911G-5HPnD is high-power unit, isn't it a problem of overheating ? Try to use bigger enclosures for the installation, or make some ventilation like a fan or something.

mfowler,
Which RouterOS version and which firmware version is installed on your RB911G?

It should have RouterOS v6.1 and make sure firmware is upgraded to 3.07

Now I have replaced the cable as well. I am still getting random drops on the LAN interface of the 911 to 750. They are fewer than they used to be but still there.

Can you not use a POE on the gigabit interfaces to power the 911 boards or something?

Does anyone have any ideas. All equipment changed out and still issues. This has to be a software bug since it was working fine until I switched to a 911 board.

hi.... what is your latest updated on the issue?

i plan to build a back haul of 16kms with the 911 boards and this topic has freezed my decision temporarily.

UPDATE

I found that the bulk of my problems were unrelated to the 911 board itself. It was a routing OSPF issue.

However, I still cannot get the board to negotiate gigabit speeds with a 750GL. My board has the latest RouterOS 6.1 with 3.07 firmware. Currently the gigabit thing isn't a big deal to me however I would like to see this work for future use. I haven't had the time to test this fully but I assume that I won't have as many issues with gigabit if I weren't using a POE adapter and powered the board from the power receptacle instead.

I am using the 911 boards on multiple links right now and they are working great. No problems at all.

Are you using a gigabit injector? We have even had a few gigabit injectors from MikroTik be bad.

I need to try a different POE injector I guess. The extra ones I have tried are not mikrotik specific gigabit adapters.

I cannot get a 433gl board to auto negotiate to gigabit when connected to a gigabit SAF link. I get the gigabit connection on the other end of the saf link that is connected to a cloud router, length of cable there is 85' of tough cable going through a gigabit Ethernet lightning suppressor. I have tried various POE's. I have plugged the saf that goes into the 433GL into a gigabit switch and it negotiates to gigabit. Length of cable is less than 5' and is tough cable and it to goes through a gigabit lightning suppressor. I need the gigabit to work otherwise the additional bandwidth the saf link can provide is not useable.

Also as an aside I have a rb911g board connected to the 5 port mt poe injector ap thing (can give the model though) that will not auto-negotiate to gigabit either using tough cable that is 3' or less. When I try to force gigabit on the "ap thing" I have to reset the board because it locks me out because my laptop may not be gigabit.

GL is of the latest firmware vintage, as is the 911 board and "ap thing", which btw, is the OmniTik Outdoor 5GHz MIMO AP

Any ideas?

You really do have to use the Mikrotik Gigabit POE adapters in order to get the gigabit negotiations. I will say that you will never see true gigabit performance since two of the pairs are being used to power the board.

I would try using as few parts as possible to test this and add parts as you see positive gigabit results. You will need to make sure that your laptop has a gigabit NIC in it.

On a side note, I have seen where mikrotiks do not always like being forced to a negotiation unless that speed will auto negotiate. It sounds to me like your laptop may not be gigabit.

I cannot get a 433gl board to auto negotiate to gigabit when connected to a gigabit SAF link. I get the gigabit connection on the other end of the saf link that is connected to a cloud router, length of cable there is 85' of tough cable going through a gigabit Ethernet lightning suppressor. I have tried various POE's. I have plugged the saf that goes into the 433GL into a gigabit switch and it negotiates to gigabit. Length of cable is less than 5' and is tough cable and it to goes through a gigabit lightning suppressor. I need the gigabit to work otherwise the additional bandwidth the saf link can provide is not useable.

Also as an aside I have a rb911g board connected to the 5 port mt poe injector ap thing (can give the model though) that will not auto-negotiate to gigabit either using tough cable that is 3' or less. When I try to force gigabit on the "ap thing" I have to reset the board because it locks me out because my laptop may not be gigabit.

GL is of the latest firmware vintage, as is the 911 board and "ap thing", which btw, is the OmniTik Outdoor 5GHz MIMO AP

Any ideas?

I will try powering the board with the jack and eliminate the POE. Thanks for the idea.

I cannot get a 433gl board to auto negotiate to gigabit when connected to a gigabit SAF link. I get the gigabit connection on the other end of the saf link that is connected to a cloud router, length of cable there is 85' of tough cable going through a gigabit Ethernet lightning suppressor. I have tried various POE's. I have plugged the saf that goes into the 433GL into a gigabit switch and it negotiates to gigabit. Length of cable is less than 5' and is tough cable and it to goes through a gigabit lightning suppressor. I need the gigabit to work otherwise the additional bandwidth the saf link can provide is not useable.

Also as an aside I have a rb911g board connected to the 5 port mt poe injector ap thing (can give the model though) that will not auto-negotiate to gigabit either using tough cable that is 3' or less. When I try to force gigabit on the "ap thing" I have to reset the board because it locks me out because my laptop may not be gigabit.

GL is of the latest firmware vintage, as is the 911 board and "ap thing", which btw, is the OmniTik Outdoor 5GHz MIMO AP

Any ideas?

I will try powering the board with the jack and eliminate the POE. Thanks for the idea.

that did it. power by jack and the 433gl goes to gigabit