OK, we have here 5 DCs controlers. One of them is trhough a firewall wi th the other 4. If I, from my windows client PC using nslookup I can resolv the records A of the 5 DCs with no problem, but when I try to resolv the PTR record of the 5 DCs, the last one (through the firewall) does not work. The other 4 DCs works fine.
Which protocol is needed to be opened in the firewall to make the nslookup working fine?
I think the problem is the replication between the first 4 Dcs and the 5th server in the other side.