Problems with reverse DNS to unknown hostname

Question

I test it in pingdom on dns health. Pingdom gives me this error message;

Reverse for 192.0.2.4 points to an unknown host name (192-0-2-4.rev.example.invalid).
The PTR record for the address points to an unknown host name.

My named.conf.local file;

 zone "example.com"{

     type master;
     file "/etc/bind/zones/db.example.com";
};

zone "2.0.192.in-addr.arpa"{
   type master;
   file "/etc/bind/zones/db.2.0.192";

};

My zones/db.2.0.192 files;

 ;
 ; BIND reverse data file for local loopback interface
 ;
 $TTL   604800
 @  IN  SOA example.com. root.example.com. (
          2016103001        ; Serial
         604800     ; Refresh
          86400     ; Retry
        2419200     ; Expire
         604800 )   ; Negative Cache TTL


 @       IN      NS      ns1.example.com.
 @       IN      NS      ns2.example.com.

 ;ns1.example.com.        IN      A       192.0.2.4
 ;ns2.example.com.        IN      A       192.0.2.4

;example.com.    IN      NS      ns1.example.com.
;example.com.    IN      NS      ns2.example.com.

2.0.192.in-addr.arpa.   IN  PTR example.com.
2.0.192.in-addr.arpa.   IN  PTR ns1.example.com.
2.0.192.in.addr.arpa.   IN  PTR ns2.example.com.

My zones/db.example.com files;

 $TTL    86400
 @       IN      SOA     ns1.example.com. root.example.com. (
                          3         ; Serial
                     604800         ; Refresh
                      86400         ; Retry
                    2419200         ; Expire
                     604800 )       ; Negative Cache TTL

 example.com.   IN  NS  example.com.
 example.com.   IN  A   192.0.2.4

 www.example.com.   IN  A   192.0.2.4
 ns1.example.com.   IN  A   192.0.2.4
 ns2.example.com.   IN  A   192.0.2.4

 example.com.   IN  NS  ns1.example.com.
 example.com.   IN  NS  ns2.example.com.

 cdn.example.com. IN  CNAME   xx.xx.example.com.

; MX records
@   IN  MX  1   mx.example.com.
@   IN  MX  2   mx2.example.com.

Also I run this command; service bind9 status

Gives this message;

 bind9.service - BIND Domain Name Server
 Loaded: loaded (/lib/systemd/system/bind9.service; enabled)
 Drop-In: /run/systemd/generator/bind9.service.d
      └─50-insserv.conf-$named.conf
 Active: active (running) since Tue 2017-01-03 23:15:31 CET; 7s ago
 Docs: man:named(8)
 Process: 29801 ExecStop=/usr/sbin/rndc stop (code=exited, status=0/SUCCESS)
 Main PID: 29806 (named)
 CGroup: /system.slice/bind9.service
       └─29806 /usr/sbin/named -f -u bind

Jan 03 23:15:32 jtx named[29806]: zone 127.in-addr.arpa/IN: loaded serial 1
Jan 03 23:15:32 jtx named[29806]: zone example.com/IN: loaded serial 3
Jan 03 23:15:32 jtx named[29806]: /etc/bind/zones/db.2.0.192:33: ignoring out-of-zone data (3.2.1.in.addr.arpa)
Jan 03 23:15:32 jtx named[29806]: zone 255.in-addr.arpa/IN: loaded serial 1
Jan 03 23:15:32 jtx named[29806]: zone 2.0.192.in-addr.arpa/IN: loaded serial 2016103001
Jan 03 23:15:32 jtx named[29806]: zone localhost/IN: loaded serial 2
Jan 03 23:15:32 jtx named[29806]: all zones loaded
Jan 03 23:15:32 jtx named[29806]: running
Jan 03 23:15:32 jtx named[29806]: zone example.com/IN: sending notifies (serial 3)
Jan 03 23:15:32 jtx named[29806]: zone 2.0.192.in-addr.arpa/IN: sending notifies (serial 2016103001)

These are the file contents. I'm not very good at DNS management. I am using the Debian operating system and the Bind9 DNS manager. I'm sure there are many errors in the files.

Thank you in advance for your help.

--Updated

Also I check in this command;

 dig -x 192.0.2.4

Returns;

 ;; OPT PSEUDOSECTION:
 ; EDNS: version: 0, flags:; udp: 4096
 ;; QUESTION SECTION:
 ;4.2.0.192.in-addr.arpa.    IN      PTR
 ;; ANSWER SECTION:
 1.2.3.in-addr.arpa. 83415 IN    PTR     4.2.0.192.rev.poneytelecom.eu.
 ;; AUTHORITY SECTION:
 192.0.2.in-addr.arpa. 83415 IN      NS      nsb.online.net.
 192.0.2.in-addr.arpa. 83415 IN      NS      nsa.online.net.

Did you check if your server is the nameserver for 3.2.1.in-addr.arpa? If you do DNS check on pingdom for 3.2.1.in-addr.arpa., does it return your server, or some other server, like your ISP — ralz, Jan 03 '17 at 22:39
I check now. 3.2.1.in-addr.arpa gives online.net Also I check in this command; dig -x 1.2.3.4. I insert this return message in post. — berk, Jan 03 '17 at 22:47

score 4 · Accepted Answer · edited Jan 06 '17 at 01:12

4

You get the message that it points to an unknown hostname, because 192-0-2-4.rev.example.invalid doesn't have any DNS records, and doesn't point to any IP.

As you pasted, nameservers for PTR are nsb.online.net, and nsa.online.net, so those nameservers are ones responsible for defining the value of PTR record.

You either need to ask you ISP/Hosting provider to change the PTR record to the hostname that has a matching A record, or ask them to set the nameservers for 2.0.192.in-addr.arpa. to the IP of the server, where you have the zone 2.0.192.in-addr.arpa you pasted in your post, if you want to be able to define PTR records yourself.

edited Jan 06 '17 at 01:12

aseq

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answered Jan 03 '17 at 22:53

ralz

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Thank you for message. "to the IP of the server, where you have the zone 3.2.1.in-addr.arpa you pasted in your post, if you want to be able to define PTR records yourself." How do I do that? Sorry. I am not very knowledgeable about these issues. I have to ask. – berk Jan 03 '17 at 23:49
2

You would need to ask subnet owner to change nameservers to your server, which is not likely they will do. Just ask your ISP/Hosting provider, whoever gave you the IP, to set the PTR to the value you want. – ralz Jan 03 '17 at 23:56

Problems with reverse DNS to unknown hostname

1 Answers1