You basically had a problem related to a DNS server, so you thought that Server Fault was the place to ask for help. In reality it's more related to workstations, i.e. try asking on Super User or Unix & Linux Stack Exchange.

I suggest having a look at dnsmasq [1]:

> -S, --local, --server=[/[<domain>]/[domain/]][<ipaddr>[#<port>][@<source-ip>|<interface>[#<port>]]

> Specify IP address of upstream servers directly. Setting this flag does not suppress reading of /etc/resolv.conf, use --no-resolv to do that. If one or more optional domains are given, that server is used only for those domains and they are queried only using the specified server. This is intended for private nameservers: if you have a nameserver on your network which deals with names of the form xxx.internal.thekelleys.org.uk at 192.168.1.1 then giving the flag --server=/internal.thekelleys.org.uk/192.168.1.1 will send all queries for internal machines to that nameserver, everything else will go to the servers in /etc/resolv.conf.

[1]: http://www.thekelleys.org.uk/dnsmasq/docs/dnsmasq-man.html

Note that the closing message didn't suggest better places to ask though. And your advice is exactly what I was looking for. Thank you.