I have i bit of a DNS issue going on at the moment that i am struggling to get my head around.
Our network has a number of sites, but only the two primary sites have AD/DNS.
Site A 172.16.0.0/16
Site B 172.18.0.0/16
I run VLANS and the above sites are broken down into /24 subnets for the different departments etc just in case your wondering.
When clients at Site B ping DOMAIN.LOCAL the reply comes from and '169.254' address, when i flush the DNS cache on the client and try again, the DNS server at that site replies. 172.16.20.1 in this case.
Quite often computers at Site A cannot reach the DNS at site A, but the DNS at Site B responds. Same thing again, if i flush the DNS cache on the client at Site A. It will then get a reply from 172.16.20.1 server at Site A.
I think the cause is more likely to be related to my lack of in depth DNS knowlege, i have probably configured something wrong at some stage during the life of this network.