DNS Problems

unameits used Ask the Experts™
I am having trouble setting up reverse DNS. MY ISP is saying they have setup everything correctly but I am getting an error when I do a dig. BAD (HORIZONTAL) REFERRAL I have two CENTOS Servers setup with 6.6 and Bind DNS. I have the reverse DNS setup on both of these dns servers and I can access everything fine when I connect directly to or

Please let me know if anyone has any ideas.

@ -x +trace

; <<>> DiG 9.8.3-P1 <<>> @ -x +trace
; (1 server found)
;; global options: +cmd
.                  21217      IN      NS      e.root-servers.net.
.                  21217      IN      NS      j.root-servers.net.
.                  21217      IN      NS      c.root-servers.net.
.                  21217      IN      NS      l.root-servers.net.
.                  21217      IN      NS      i.root-servers.net.
.                  21217      IN      NS      b.root-servers.net.
.                  21217      IN      NS      k.root-servers.net.
.                  21217      IN      NS      h.root-servers.net.
.                  21217      IN      NS      m.root-servers.net.
.                  21217      IN      NS      g.root-servers.net.
.                  21217      IN      NS      d.root-servers.net.
.                  21217      IN      NS      a.root-servers.net.
.                  21217      IN      NS      f.root-servers.net.
;; Received 228 bytes from in 34 ms

in-addr.arpa.            172800      IN      NS      b.in-addr-servers.arpa.
in-addr.arpa.            172800      IN      NS      f.in-addr-servers.arpa.
in-addr.arpa.            172800      IN      NS      e.in-addr-servers.arpa.
in-addr.arpa.            172800      IN      NS      a.in-addr-servers.arpa.
in-addr.arpa.            172800      IN      NS      d.in-addr-servers.arpa.
in-addr.arpa.            172800      IN      NS      c.in-addr-servers.arpa.
;; Received 419 bytes from in 173 ms

64.in-addr.arpa.      86400      IN      NS      r.arin.net.
64.in-addr.arpa.      86400      IN      NS      t.arin.net.
64.in-addr.arpa.      86400      IN      NS      u.arin.net.
64.in-addr.arpa.      86400      IN      NS      v.arin.net.
64.in-addr.arpa.      86400      IN      NS      w.arin.net.
64.in-addr.arpa.      86400      IN      NS      x.arin.net.
64.in-addr.arpa.      86400      IN      NS      y.arin.net.
64.in-addr.arpa.      86400      IN      NS      z.arin.net.
;; Received 179 bytes from in 187 ms

186.41.64.in-addr.arpa.      86400      IN      NS      dns03.savvis.net.
186.41.64.in-addr.arpa.      86400      IN      NS      dns02.savvis.net.
186.41.64.in-addr.arpa.      86400      IN      NS      dns04.savvis.net.
186.41.64.in-addr.arpa.      86400      IN      NS      dns01.savvis.net.
;; Received 133 bytes from in 48 ms

186.41.64.in-addr.arpa.      600      IN      NS      ns2.zooce.com.
186.41.64.in-addr.arpa.      600      IN      NS      ns1.zooce.com.
;; Received 88 bytes from in 14 ms 14400 IN      PTR      ns1.zooce.com.
186.41.64.in-addr.arpa.      86400      IN      NS      ns1.zooce.com.
186.41.64.in-addr.arpa.      86400      IN      NS      ns2.zooce.com.
;; Received 134 bytes from in 18 ms
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Distinguished Expert 2017

You seem to have a block

There is no way they could delegate you the 186.41.64.in-addr.arpa
Commonly the delegation zone name will be the range of IPs as the last octet. In your case I guess your network ip is the zone they would delegate would be
24- In ns
In this zone, you will have
26 in PTR
27 in PTR

While on their side, they would need to have entries in the following format
In the 186.41.64.in-addr.arpa zone
26 in CNAME 26.24-
Double check the name of the zone they delegated to you so that you can define it on your servers.
Distinguished Expert 2017

Did you register ns1 and ns2 with their IPd through your domain registrar?

If you could clarify what exactly your issue is as it is not clear and I am trying to cover/infer/Devine what the various possible issues.


Arnold why do you say they can't delegate 186.41.64.in-addr.arpa. I have an entire C class.

Yes both of the name servers are registered with the domain registrar.

The problem that occurs is most of the time you can not perform a reverse DNS lookup. When I attempt to with Nslookup I get  can't find Server failed
Distinguished Expert 2017

They can not delegate because of the manner in which it is registered with Arin and with them.

One option you have is to subordinate the zone such that they configure their servers to slave the zone of 186.41.64.in-addr.arpa from your servers. or have them configure the 186.41.64.in-addr.arpa as a forwarder zone to your servers,

This way on your server the zone will include their name servers in addition to yours and when you make changes, their servers will be notified of the change at which point they will trigger the update.

The issue currently is that their server is returning a negative response with a reference to your servers.

This is likely the cause for your issue. a request to an authoritative server must come with an answer.

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