Errors popping up causing BFD drop

B5c PTP.

We are seeing a rise in sp err showing up and every time this has happened we see our BFD session drop, which triggers our OSPF to go down.

We have upped our timers to 600 msec and it has to miss 3 times. so 1.8 seconds of timeout.

Anyone have any experience with this and found a work around or resolution?

I am using MRP and i’m seeing same problems since the beginning. As for now there is no workaround. Maybe support staff will look into it.

I would double check with Mimosa on the specific cause of SP errors, I want to say it has something to do with the SSID.

Could be intermittent noise on the channel, maybe try moving the link to a slightly different channel?

Yeah Ive tried a different channel setup and it seemed to resolve but only for a day.

Unfortunately the area has limited available spectrum to juggle channels around.

Are you running any other links in the area that have the same SSID?

Nope, we use a seperated SSID for each of our PTPs. ant the only other PTP to the site is a 24GHz AirFiber.

There are A5c on each site, One being a pole, the other a water tower.

SRS on the A5c’s? If SRS, do you have the B5 synced with the A5s, probably the A5s would need to be using B Gender (if the B5 local to them was not the AP of the link)…

My GoogleFu is failing me on figuring out what SP errors exactly mean.

A5c’s are SRS.

Yeah the Gender thing is setup as right as possible. I’ve been through that thing and from what I understand the timing that is used on A5 and B5 are different. That you cant sync the products perfectly. I never found a document that talked about a mixed deployment rather, it was either a B5 or A5 per tower deployment.
That may be the different nature of PTP vs PTMP.

What are the timing values you are using for the B5s?


the TDMA Window was a 8 ms and was change to 4 to see if it would make the issue get worse or better.

The AP side A5 radios are all set up in the screen below.

The A5 on the STN side are setup the same as in the screenshot below.

Ya, you won’t get the B5 to sync with the A5s unless you use an 8ms window size.

There is other information, but this is the most pertinent info regarding synchronization.