Resolv Conf Multiple DNS Servers with specific domains

Impossible to achieve using /etc/resolv.conf only.

I'd say the easiest thing is to install dnsmasq (a caching DNS client), make it the sole resolver by putting nameserver 127.0.0.1 into /etc/resolv.conf and then modify dnsmasq configuration:

• uncomment no-dhcp-interface= to disable dnsmasq's DHCP server facilities;
• add a single generic record: server=10.8.0.1;
• add specific record: server=/mydomain.local/10.250.0.2 to all requests for hosts in mydomail.local go to that server.

Actually this can be done if you are using dnsmasq.

At the bottom of your /etc/dnsmasq.conf file you can add lines like this:

server=/domain.net/172.166.7.23
server=/domain.com/142.124.17.12

I haven't tested it on more than my machine, but it works for me.

My requirement was because my VPN client was not using the correct nameservers when connected to a workplace to route internal addresses. This fixed it to use internal DNS servers for specific domains.

This could be difficult to achieve, using plain /etc/resolv.conf only, imho. Would it be a problem, to install a local resolver? If not - the following plan might be applicable:

1. Install a cache-only DNS from your distro repository. The default configuration should work and usually you have 127.0.0.1 as a listening address only.
2. Backup your existing /etc/resolv.conf and create a new one, containing barely nameserver 127.0.0.1. Test that your local DNS works correctly, resolving Internet names.
3. Put the following in the named.conf:

zone "mydomain.local" { type forward; forward only; forwarders { Your-VPN-DNS-IP; }; };

4. Test it again, both Internet and VPN resolution. If successful, you could add a search line to /etc/resolv.conf.

HTH-RB