For various reasons you may want to selectively redirect DNS queries for a specific domain to a specific server.
In my case, I had to redirect Active Directory domain DNS requests over a VPN link. The VPN was established between an ASUS RT-N10U B1 running Tomato by Shibby and an Untangle box.I wanted to forward only the domain zone and not all the entire DNS traffic not to deteriorate performances.
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Forwarding all the DNS requests over the VPn would result in decreased performances for the Branch Office users.
The solution came from the Dnsmasq in the Tomato firmware. The configuration can be found under Advanced, DHCP/DNS.
The configuration goes like this:
rebind-domain-ok=/domain.lan/ server=/domain.lan/192.168.10.10 address=/server/192.168.10.10 address=/mail/192.168.10.10
In short:
- server specifies to server for a specific domain.
- address specifies the IP of the specified FQDN
No need for a local Active Directory!
For more details about the possibilities, check the Dnsmasq documentation.