DNS Resolver appending domain to end of some outbound DNS queries

[ProxyMoron]

So i'm having intermittent DNS issues using a VPN where the VPN DNS server is the only one configured in PfSense under    System>General Setup>DNS Server 1 and the VPN gateway selected.

I did a packet trace from the router and used DNS lookup from the router and can see DNS packets sent out the VPN Gateway for port 53 and in wireshark i see that if i search for domain.com (in DNS Lookup tool) i can see requests to the VPN DNS server and responses for that specific domain, however i also see domain.com.mynet.local being requested (mynet.local being my internal domain) and this is obviously not resolved.

Why would DNS resolver be appending my internal domain name to the DNS requests? Would the fact that the DNS servers IP is a 10.x.x.x address be relevant?

Thanks folks.

[johnpoz]

well if you have a client adding its search suffix then yeah that is what it would do..

If your resolver setting is set for your local domain to be transparent..  Then yeah if does not have a record it can resolve it normally.  I have mine set to static.. So if you look for something say norecord.local.lan it will not try and resolve that.. Just sends back nx..

If your set to transparent which is the default type and you look for norecordfor.something.whatever.mynet.local then yeah it would try and resolve that upstream..