I have this problem. My WAN sites get IP addresses from the DHCP server in the datacenter. DHCP says the DNS servers are the local corporate DNS servers (also in the DC). So what happens when the tunnel from the WAN site to the DC goes down?
Users can’t even surf facebook. Oh the horror. But really, users shouldn’t have their Internet access cut off just because the DC lost power or was sacrificed to a volcano god. Especially since we use hosted services. Email should always work, even if head office is down!
What we need is for DNS requests for myspace and reddit to go to the regular public DNS server, and requests for theservers.localdomain.lan to go to the corporate DNS servers.
Turns out there’s-an-app-for-that using dns-views within the router…