Hi there,
We have a Balance 310X 5G which we have set up with the following WANs:
1 x Cellular
1 x VSAT (as backup)
2 x Starlink connections
We have two separate SFCP links, one to a public location in the UK and another using Relay mode to another Peplink device. Both these connections work perfectly 90% of the time.
However originally I had issues with one of the Starlink WANs almost always showing WAN Down. It would operate pretty well but with only one Starlink WAN active. I mostly resolved this by installing a cheap switch between one of the Starlinks and our network, as suggested by a few on the internet. This now works reliably most of the time, but from time to time I get an error on the Starlink WAN that routes via the intermediate switch: Not available - link failure, no data received. This usually occurs on only one of the SFCP links, and not the other. See below:
After more internet digging I found that this sometimes occurs when the intermediate router blocks new connections as part of a UDP flood control protection. Indeed, in the intermediate router logs I find errors 'Socket limit reached. Dropping new queries’. A restart of the router solves this for a while. What also seems to solve it is disabling the WAN on the Peplink for a few seconds and re-enabling it.
I have read that forcing the SFCP connection to use a TCP port alleviates this issue, but I can’t quite seem to get this right. If this would solve the issue, please could someone explain the correct way to achieve this?
Interesting to note that the Starlink WAN that doesn’t route via an intermediate router is rock solid. The Balance just seems to not like two direct Starlink connections simultaneously.
Would it rather be better to purchase a better quality router, that can handle more UDP traffic and potentially have the option to disable such protection?
What is the fundemental issue that requires an intermediate router to be used? Is this something that can be dealt with by a future Peplink firmware update? It seems like this is a fairly common issue with Peplink/Starlink setups.