Take the 2-minute tour ×
Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

I am having a hell of a time getting our PTR record right.

Our current PTR zone looks like this:

$ttl 38400
@   IN  SOA ns1.domain.com. admin.domain.com. (
            38400 )

xxx.xxx.xxx.in-addr.arpa.   IN  NS  ns2.domain.com.
xxx.xxx.xxx.in-addr.arpa.   IN  NS  ns1.domain.com.
97 IN PTR mail.domain.com.
xxx.xxx.xxx.xxx.in-addr.arpa.   IN  PTR mail.domain.com.
97.96/28. IN PTR mail.domain.com

For some reason the only thing that works is the 97.96/28. When this line is in there it actually says I have a PTR record when reporting from intodns.com. If I remove that line, it says I have no PTR.

I have followed instructions from http://www.philchen.com/2007/04/04/configuring-reverse-dns and when I follow those instructions intodns.com says I have no PTR.

When it does work with the line 97.96/28., the PTR kicks back as (from intodns.com) :

97.xxx.xxx.xxx.in-addr.arpa ->  mail.domain.com.xxx.xxx.xxx.in-addr.arpa

Which is, to my knowledge, an incorrect PTR. I want it to just kick back as mail.domain.com, without the xxx.xxx.xxx.in-addr.arpa extension.

I have tried everything I can think of but I can't fix it. I can't help but think it's one of those things that is so stupid and simple I'm going to do the ol'facepalm.

Any help is greatly appreciated. Thanks!

In the event that the domain zone is needed, here it is:

$ttl 38400
@   IN  SOA domain.com. supadmin@domain.com. (
            38400 )
domain.com. IN  A   xxx.xxx.xxx.xxx
www.domain.com. IN  A   xxx.xxx.xxx.xxx
ftp.domain.com. IN  A   xxx.xxx.xxx.xxx
m.domain.com.   IN  A   xxx.xxx.xxx.xxx
localhost.domain.com.   IN  A
webmail.domain.com. IN  A   xxx.xxx.xxx.xxx
admin.domain.com.   IN  A   xxx.xxx.xxx.xxx
mail.domain.com.    IN  A   xxx.xxx.xxx.xxx
domain.com. IN  MX  5 mail.domain.com.
domain.com. IN  TXT "v=spf1 a mx a:domain.com ip4:xxx.xxx.xxx.xxx ?all"
domain.com. IN  NS  ns1
domain.com. IN  NS  ns2
ns1 IN  A   xxx.xxx.xxx.xxx
ns2 IN  A   xxx.xxx.xxx.xxx

Any double entries in different formats were part of my troubleshooting process.

share|improve this question
Did you try to delete the last two lines from the PTR zone file? –  Khaled Nov 30 '10 at 19:31
You get the invalid PTR as there is no dot at the end of your record (97.96/28. IN PTR mail.domain.com). –  whitequark Nov 30 '10 at 19:36
@Khaled - Yes. When I delete those last 2 lines, it tells me I have no PTR record. It only reports having a PTR record if I use the 97.96/28. –  Physikal Nov 30 '10 at 19:49
@ whitequark - When I add a . at the end of the line you specify, my PTR report still comes back with the mail.domain.com.xxx.xxx.xxx.in-addr.arpa instead of just mail.domain.com. Any ideas? –  Physikal Nov 30 '10 at 19:50

1 Answer 1

Here is a copy of my rev zone/ptr

zone "10.168.192.in-addr.arpa" IN {
  type master;
  file "mysite.gr.rev.zone";
  allow-update { none; };

$TTL 86400
@     IN     SOA    ns1.mysite.gr.     postmaster.mysite.gr. (
                2001062501 ; serial
                21600      ; refresh after 6 hours
                3600       ; retry after 1 hour
                604800     ; expire after 1 week
                86400 )    ; minimum TTL of 1 day

      IN     NS     ns1.mysite.gr.
      IN     NS     ns2.mysite.gr. 
142   IN     PTR    ns1.mysite.gr.
10    IN     PTR    webmail.mysite.gr. <------ the dot at the end.

btw, when you made any change on dns, you stop and restart service?

share|improve this answer
To me, that looks almost the same as what I have. I added the . at the end which I was missing, but nothing changed. I'm still having the same issue. –  Physikal Dec 3 '10 at 16:45
And yes I am stopping - restarting Bind after each change. –  Physikal Dec 3 '10 at 16:46
Physikal, what's your zone definition in named.conf? What's the zone range? How it was declared? –  Denis Dec 3 '10 at 17:32
zone "xxx.xxx.xxx.in-addr.arpa" { type master; file "/var/named/xxx.xxx.xxx.in-addr.arpa.hosts"; }; –  Physikal Dec 3 '10 at 20:15
Bloody hell....I figured it out. The 97 needs a period. So, 97. –  Physikal Dec 3 '10 at 22:59

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.