OpenVPN on any device- only forward DNS

Question

I'm exploring all the different things that I can do with OpenVPN and one of the top questions is regarding DNS.

I have a raspberrypi at home with openvpn and the openvpn client on my idevices.

Everything works perfectly. However, all traffic is tunneled. While this is ok, what i'd prefer is to only tunnel the DNS and anything destined for the local network.

For example, if I wanted to stream netflix, there's no reason to pass all of this traffic over the tunnel (bandwidth isn't an issue so much as cpu power...).

Any ideas? I suspect it can be done (cloudflare as a "vpn" dns only service for example).

Thanks!

Answer 1

I found part of the answer here: https://docs.pi-hole.net/guides/vpn/dual-operation/

push "route 192.168.2.0 255.255.255.0"
push "dhcp-option DNS 192.168.2.123"

and commented out this:

#push "redirect-gateway def1 bypass-dhcp"

This works great- DNS via the vpn tunnel and traffic through the local non tunnel....

However...i cannot access the network that I initiated the VPN from (despite the fact that the traffic is clearly going through it).

I suspect I can add a route, however since the local network changes, im not sure how to do this.

I'll post another question since it's technically another issue.