vincenzo romero wrote: > Hello all, > > I am trying to configure a subdomain DNS server on a Cent OS 5.1 - for > my lab. Brief configuration: > > Lab machine ---> 192.168.17.2 (should respond to DNS queries from > hosts in 192.168.16.0/20 network) > > 1. I would also like to forward any queries outside the above network > to our corporate domain (no firewalls between our 192.168.16.x network > and the corporate network. The domain server is: dns.company.com > with an IP of 10.100.1.2 (255.255.255.0). > > 2. What I have configured is: > > 192.168.17.2 --> myhost.lab.company.com > 10.100.1.2 --> dns.company.com > > 3. Installed the dns bind 9 in myhost and set basic configuration via > the system-config-bind GUI. My configuration file specific to my > setup there is: > > cat lab.maxiscale.com.db > $TTL 1H > @ SOA myhost.lab.company.com. > root.myhost.lab.company.com. ( 2 > 3H > 1H > 1W > 1H ) > NS myhost.lab.company.com. > qaserver2 A 192.168.17.3 > qaserver1 A 192.168.17.1 > myhost A 192.168.17.2 > > ================= > > The rest of the DNS/Bind records were based upon the auto-generated > files from the Bind GUI Config tool. > > 3. I also changed myhost's resolv.conf to reflect the following: > > search lab.mycompany.com > 192.168.17.2 > search mycompany.com > 10.100.1.2 > what's this? should be: search lab.mycompany.com mycompany.com server 192.168.17.2 server 10.100.1.2 > ====== > > PROBLEM: > > 1. When I am in myhost.com, I can perform: > a. nslookup hostname (to any host within 192.168.x and 10.100.x networks) > b. nslookup ip to anyhost wtihin both networks. > > 2. When I am in one of the hosts within 192.168.x aside from > myhost.com (for example, qaserver1 or qaserver2): > > a: SUCCESS to nslookup hostname to any host within BOTH networks. > b. FAILS to nslookup ip (reverse nslookup) to anyhost within the > 10.100.x network. > you did not create the reverse zone. the zone file should contains something like $TTL 1H @ SOA myhost.lab.company.com. root.myhost.lab.company.com. ( 2 3H 1H 1W 1H ) NS myhost.lab.company.com. 3 IN PTR qaserver2.lab.company.com. 1 IN PTR qaserver2.lab.company.com. 2 IN PTR myhostA.lab.company.com. WARNING. don't forget the trailing dot (...lab.company.com. with a dot at the end). you must tell you bind that it is authoritative for this zone. so in named.conf, add zone "17.168.192.IN-ADDR.ARPA" { type master; file "192.168.17.db"; }; where 192.168.17.db is the name of the zone file. A good reference for DNS is http://www.zytrax.com/books/dns/