Systems are all Centos 6.2 Lets say I have a masterdns with IP 10.2.1.2, authoritative for the 10.2.1.X subnet and let say it is domain example.com I have another two subnets, 10.2.2.X and 10.1.2.X Each one has its own DNS server, dns2 and dns1 respectively and let say these are domains dom2.example.com and dom2.example.com respectively. The masterdns server has slave zones for dns1, dns2 and respond to requests OK. The dns1, dns2 have the masterdns zones as slaves two, and respond to requests OK. So, the masterdns has as slave zones all the subordinate domains of example.com Each of dns1 and dns2 use masterdns as a forwards (which uses another dns cache/proxy server) for dns resolution of internet public domain names. It works OK that too.

The problem is, and I cannot figure it out. Why queries for example at dns1 for hostnames of dom2.example.com do not resolve? If i use nslookup - masterdns at dns1 server, resolve (i use directly the dns facility of masterdns). If I use nslookup locally, meaning queries are sent to dns1, for hosts that are at dom2.example.com, they do not resolve. Everything other works OK.