internal DNS not resolving on Windows VM

[tomatoandcake]

Hi all,

as the title notes - I'm not able to use my internal domain to resolve my NAS from a Windows VM I have on it.

I can access everything using the IP address (NAS login, docker containers etc) but I cannot resolve them via my internal domain.

The internal DNS IP is showing in network connections, but when I try reaching my NAS via the domain, it fails.

I've tried manually adding it, and having it auto-add from my router.

My VM is running on the standard "default VM network".

 

[fredbert]

Welcome to the forum.

Where are you getting DNS resolution for your personal domain? If it m an Internet located DNS server then your router will have to support local loopback to route back from the Internet IP to the LAN IP. I think it will probably also require a port forward rule too.

Do you run an internal DNS server?

 

[tomatoandcake]

Hi there,

Thanks for the welcome!

Yes, I'm running an internal DNS to resolve my internal domain. Works everywhere apart from the Windows VM.

However, since posting I've realised it's the Proton VPN I have running in Windows. I have it set to split-tunnel and only port one app through it - but even when that is on, my internal DNS does not resolve. As soon as I turn off that VPN, I can resolve my internal domain.

So I suspect I'll have to do some more digging into this Proton VPN app, as it seems to be the culprit.

 

[fredbert]

Sounds likely. If the VPN connection fully encapsulates the Windows VM connectivity towards Proton VPN then you won't get access to local services. But if not then you should check routing and other network settings too. Is your internal domain purely used internally or do you have it publicly resolving too?

In Windows you can test DNS resolution via cmd.exe or Power Shell. Using nslookup in interactive mode can help to see which DNS servers you can access and how they resolve names. [I'm not sure if Windows has the dig command]

$ nslookup
set all
www.mydomain.com
... output of domain resolution
... using device DNS config
server 192.168.a.b
www.mydomain.com
... output of domain resolution
... using my local DNS server
exit