Wireguard clients not resolving DNS

Technical Support for Routers VPN, DNS, Leaks
1

Hi there!

I have a GL-AR750 router with the latest firmware version available (4.3.17).

I've noticed that since upgrading from version 3.x to 4.x, the WireGuard client doesn't seem to be working properly.

Symptoms:

  • The WireGuard client connects successfully to the WG server.
  • When using SSH directly from the router, I can resolve DNS queries from my local DNS server (pfSense).
  • Lan clients connected to the router can ping IPs on my WG home LAN and IPs outside my WG home LAN, so the connection is being routed through WG. However, it seems that clients can't resolve DNS queries.

I've read some possible solutions on the forum, such as disabling DNS rebinding or erasing the 'lan' namespace, but nothing seems to work.

When using the same WG profile directly on other devices such as PCs, phones, etc., everything works fine, including DNS resolution (with locally defined hostnames).

Any help would be greatly appreciated.

Thanks in advance!

2

I have just found the solution: setting the MTU to 1380 did the trick. I still don't know why this value isn't automatically set to the correct one :frowning:

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