Wireguard: Switch server when current server has high utilization

[paprika555 1]

Hello,

i'm using airvpn to open my plex server for friends (ds-lite double-nat issue) with wireguard which works really well.
The issue i'm facing is that sometimes, when the current server has a very high utilization (maxed out network speed), the vpn speed goes down and nobody is able to stream.
After switchting the server (e.g. wg-quick down/up), everything works fine again.

My question is, is there an solution possible with wireguard? If not, i'm thinking about querying the current server with the API and restart wireguard when the current server reaches near 100%, but that would drop the connection if a movie is played.

Thanks, happy to hear some ideas.

paprika

Edited ... by paprika555

[benfitita 39]

To switch to less loaded server, you could add to cron something like this: https://github.com/WireGuard/wireguard-tools/blob/master/contrib/reresolve-dns/reresolve-dns.sh. As long as you're using peers with FQDN, for example us3.vpn.airdns.org, this script will ask wireguard to reresolve this domain. This domain resolves to the "best" server in a given country. "best", I believe, means least loaded and without connectivity issues.

However, this often will change your AirVPN server, so this means dropped connections and some time until DDNS entry updates or some other means to tell your friends the new IP.

[paprika555 1]

Thanks for the response @benfitita. I've now tracked the utilization of the current server i'm connected to, and the plex clients are still not able to play the videos even when the utilization is only 5%.
A reconnect does not solve the issue. There seems some kind of throttling going on, but only sporadically. Very strange.

[benfitita 39]

It might be your ISP messing with your internet connection. To verify this, try OpenVPN on port 443. It is a common port used for HTTPS, so ISPs usually don't bother with throttling it.

[Air4141841 25]

sounds like a MTU issue to me.
Staff has said if using us3.vpn.airdns.org:1637. as the connected server.  it will automatically connect and reconnect if there is an issue.
I've noticed when I used wireguard that was true.   I would be on one server, then check the IP then be on a different one.
the entire point of WG was to be a connectionless protocol.  if its disconnecting its on your configuration end 

[benfitita 39]

Sure, that could be an MTU issues as well. Worth trying 1280.

However, I'm not entirely sure that WireGuard automatically re-resolves the peer FQDN when connectivity issues happen. I think you need to actively nudge it to re-resolve and therefore pick up a new server. Otherwise scripts like I linked above wouldn't be needed.

Edited ... by benfitita
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