GL .iNet VPN Client slow during certain time of day

Technical Support for Routers
1

Hello,

I have a GL.iNet GL-AXT1800 VPN server (at home) and a GL-AXT1800 VPN client travel router. They are configured with Wireguard VPN. My travel router is with me for the time being in India, and my VPN server is in the States. For a few days now, I have noticed that between 7:30am CT and 11:30am CT, the travel router speeds are very slow. I get <1Mbps download and >15Mbps upload speeds. Outside of this window, the speed is >40Mbps dowbload and >30Mbps upload.

I have checked the local internet speed during this time, and it is around 100Mbps download and >50Mbps upload. My home internet speed during this time (where the VPN server is) is around 500Mbps download and >85Mbps upload. During this time, I have restarted all components - my home cable modem, router, VPN server, local router and travel router. But the problem still prevails until it is 11:30am CT.

My travel router and server router MTU values are set at 1420, respectively.

Any idea what could be going on? Any help would be greatly appreciated.

2

I assume the issue is WireGuard. WireGuard uses UDP and UDP will get lost if there is much traffic on some lanes. So the first thing that gets worse when there is too much traffic: UDP like phone calls (SIP) or WireGuard VPN.

You could try to switch to OpenVPN TCP for some testing.

3

This seems to have worked. It's only been the third day, however OpenVPN does have consistent speeds. But OpenVPN speed is almost half of WireGuard.

4

Yep, that's the downside here.