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reverse DNS in LINUX

I was having problem with setting up reverse DNS entries for my IP address.
the IP provider has agreed to relay their reverse query to 2 nameserver ns1.domain.com and ns2.domain.com

these 2 name servers are INITIALLY located at 1 IP, However, I recently changed them to other locations: ns1.domain.com --> ip1, and ns2.domain.com --> ip2. I also have 2 dns servers at those 2 ips, running BIND.

What should I configure for BIND in order to handle reverse look up?
here is my zone file:

xxx.xxx.xxx.in-addr.arpa. IN      SOA     ns1.domain.com. admin@domain.net. (

                                                               1999040701 ;Serial number
                                                               10800      ;Refresh
                                                               3600       ;Retry
                                                               604800     ;Expire
                                                               86400)     ;Minimum TTL
@                       IN      NS      ns1.domain.com.
@                       IN      NS      ns2.domain.com.
xxx                      IN      PTR     cpanel.domain.net.

are those looking correct?. Because, PTR looking still fails at this time ;(

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2 Solutions
That looks right except for the @ sign in the email should be a period, I don't think the @ sign is supported.

When you start bind or reload the zone does it say that it loaded correctly?  If yes, can you do an nslookup on the IP against the your new servers directly with "nslookup xxx.xxx.xxx.xxx ns1.domain.com" and does that return the correct information?

If all of that checks out then contact your ISP.  Reversing less than a class-c is not supported and there are various ways to handle it - I would think that they would be slaving to a specific IP address and you moved your name servers from one location to another - just changing the name isn't enough, they'll need the new IPs.

Hope that helps - post the output from your bind log when you start it up or reload the zone if you can't figure it out.
Correct, use a . in the admin email, not a @

If the zone loads cleanly and everything looks ok at the server end, try using the reverse lookup feature on www.dnsstuff.com  - it's quite useful and shows the whole trace. Good for fault-finding.
valleytechAuthor Commented:
after using "nslookup xxx.xxx.xxx ns1.domain.net" (right at the DNS itself), i got this
xxx.xxx.xxx.in-addr.arpa       name = cpanel.domain.net.

the bind returns ok
Oct  3 15:10:04 ns1 named[2373]: no IPv6 interfaces found
Oct  3 15:10:04 ns1 named: named reload succeeded

i'd like have reverse record for xxx.xxx.xxx.xxx. I've requested the PROVIDER for that IP to point their PTR query to where my dns resides (technically, another IP provider). Will it work that way?

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Thats really a question that only your ISP can answer.  Do they support classless reverse delegation?  If so, just ask them to delegate the reverse to your dns servers.
valleytechAuthor Commented:
the dnsstuff reverse query still showed that the ns1.domain,net still resides that the old IP which is not correct because I have made changes days before.
Is it problem caused by DNS cache? it's been 48 hours already
valleytechAuthor Commented:
thanks again!! it finally works

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