DNS on Linux stopped working without Air

[Biggsboy 0]

Hello, I'm currently running Ubuntu Mate 22.04 and using the Eddie client for Air.

Eddie works great on its own, but its seems that my DNS does not work unless I'm connected to the VPN. I've done the normal troubleshooting steps: ran updates, restarted computer, restarted NetworkManager, and tried setting the DNS server to 8.8.8.8 using nmtui. Nothing seems to resolve it and I've tried this on two networks (so it's not just my home network causing the issue).

I previously noticed this happening but a restart or two of my machine fixed it; now it seems permanent. Any advice would be greatly appreciated, i'm still fairly new to Linux!

[Tech Jedi Alex 1518]

Provide a system report..

[Biggsboy 0]

Here it is, thanks!

EddieReport12.24.25

[Tech Jedi Alex 1518]

Eddie version: 2.21.8

Let's update Eddie first to the current stable, which is 2.24.6. 
 

Detected DNS: 10.128.0.1, fd7d:76ee:e68f:a993::1

Also, connect, then disconnect. We're troubleshooting DNS not being reset to the original setting after disconnection; it's expected that AirDNS is still set when you're connected.

[Biggsboy 0]

My apologies, this should be the correct report now!

I've updated the Eddie client, rebooted, and connected and then fully disconnected before generating this one.

EddieReportv2.txt

[Tech Jedi Alex 1518]

Detected DNS: 100.100.100.100
[…]
. 2025.12.26 09:44:51 - DNS of the interface 'wlp3s0' restored to '8.8.8.8 192.168.1.1' - via systemd-resolved

Eddie restores the DNS to the setting it seemed to detect before which is correct, but then 100.100.100.100 is set, which seems to be a Tailscale thing. It is said that this is used as a "127.0.0.1 for Tailscale services". It is also said that Tailscale is listening on port 53 to resolve things. Eddie detected systemd-resolved, so I cannot help but wonder whether you're using two DNS resolvers racing each other. Maybe refer to the Tailscale documentation on how to run Tailscale with a VPN. Maybe someone else with experience can chip in, too.