I confirm that frequent disconnects while using a 5G mobile network are due to aggressive CGNAT policies and short NAT timeouts (often 30–60 minutes) from my carrier.
I found that enabling Tailscale alone wasn't enough. To achieve a stable connection, I had to manually adjust the following settings on my router Spitz AX (GL-X3000):
-
Lower the MTU: Change the MTU (Maximum Transmission Unit) from 1500 to 1350.
-
Force IPv4: Switch the Protocol Mode from "Dual Stack (IPv4/IPv6)" to IPv4 Only.
-
Persistent Keep-Alive: Set the "Ping Host" (Keep-Alive) function to a custom interval of 10s.
Suggestion for developers
While Comet 5G GL-RM10RC is coming, many it’s users will encounter these carrier-specific CGNAT issues. It would be a great quality-of-life improvement if the GL Cloud could automatically detect or handle these short NAT timeouts to avoid the need for manual router adjustments.