Reverse DNS Dig returning PTR results only with trace option

Raj Adhikari raj at cyzap.com
Wed Nov 11 00:29:09 UTC 2009


Kevin Wrote: {QUOTE} There is no "BIND way" versus "Windows way". For a
range smaller than /24 you either need to host all the records in the
/24 zone, delegate each entry individually (as /32 zones), or use
CNAMEs. This is determined by the protocol, regardless of whether you're
using Microsoft DNS, BIND or any other implementation.

Note that many thousands (tens of thouands? hundreds of thousands?) or
organizations use RFC 2317 for their reverse DNS without issues. So, on
what do you base your assessment of this approach as having "lots of
problems"? The folks who published RFC 2317 actually know what they're
talking about. People complaining on forums about having botched their
RFC 2317 configs, probably *don't*.
{QUOTE}

Ok, moving to RFC 2317, I may not have configured them correctly. If RFC
2317 will work for me then that would be great. This time I took the
subnet 64.253.134.176/28. This block needs to be delegated from
ns1.cyzap.net to ns1.moneytreesystems.com
I followed this for the configuration and naming convention from
http://support.microsoft.com/kb/174419.
I configured at ns1.cyzap.net as:
;  Database file 134.254.63.in-addr.arpa.dns for 134.254.63.in-addr.arpa
zone.
;      Zone version:  ................
;

@                       IN  SOA ns1.cyzap.net.  .............. (
                           ....
                            ...
;
;  Zone NS records
;

@                       NS    ns1.cyzap.net.
@                       NS    ns2.cyzap.net.

;  Delegated sub-zone:  176-28.134.254.63.in-addr.arpa.
;
176-28                  NS    ns1.moneytreesystems.com.
ns1.moneytreesystems.com. A    63.254.134.213
ns1.moneytreesystems.com. A    63.254.134.214
;  End delegation
177                     CNAME    177.176-28.134.254.63.in-addr.arpa.

========================================================================
And at ns1.moneytreesystems.com, the configuration is as:
;
;  Database file 176-28.134.254.63.in-addr.arpa.dns for
176-28.134.254.63.in-addr.arpa zone.
;      Zone version:  xxxxxx
;

@                       IN  SOA ns1.moneytreesystems.com. 
hostmaster.moneytreesystems.com. (
                            .....
                            .....
;
;  Zone NS records
;

@                       NS    ns1.moneytreesystems.com.
ns1.moneytreesystems.com. A    63.254.134.213

;
;  Zone records
;

177                     PTR    testnew177.cyzap.net.

========================================================================
My dig output for this are:
$ dig @ns1.cyzap.net -x 63.254.134.177

; <<>> DiG 9.4.2 <<>> @ns1.cyzap.net -x 63.254.134.177
; (1 server found)
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 50666
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;177.134.254.63.in-addr.arpa.   IN      PTR

;; ANSWER SECTION:
177.134.254.63.in-addr.arpa. 3600 IN    CNAME  
177.176-28.134.254.63.in-addr.arpa.
177.176-28.134.254.63.in-addr.arpa. 60 IN PTR   testnew177.cyzap.net.

;; Query time: 3 msec
;; SERVER: 172.30.111.3#53(172.30.111.3)
;; WHEN: Tue Nov 10 18:06:59 2009
;; MSG SIZE  rcvd: 104
============================
$ dig @ns2.cyzap.net -x 63.254.134.177

; <<>> DiG 9.4.2 <<>> @ns2.cyzap.net -x 63.254.134.177
; (1 server found)
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 58836
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;177.134.254.63.in-addr.arpa.   IN      PTR

;; ANSWER SECTION:
177.134.254.63.in-addr.arpa. 3600 IN    CNAME  
177.176-28.134.254.63.in-addr.arpa.
177.176-28.134.254.63.in-addr.arpa. 55 IN PTR   testnew177.cyzap.net.

;; Query time: 0 msec
;; SERVER: 172.30.111.53#53(172.30.111.53)
;; WHEN: Tue Nov 10 18:20:13 2009
;; MSG SIZE  rcvd: 104



==========================
$ dig -x 63.254.134.177

; <<>> DiG 9.4.2 <<>> -x 63.254.134.177
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 60512
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;177.134.254.63.in-addr.arpa.   IN      PTR

;; ANSWER SECTION:
177.134.254.63.in-addr.arpa. 2985 IN    CNAME  
177.176-28.134.254.63.in-addr.arpa.

;; Query time: 0 msec
;; SERVER: 172.30.111.254#53(172.30.111.254)
;; WHEN: Tue Nov 10 18:07:18 2009
;; MSG SIZE  rcvd: 70
===================================
$ dig -x 63.254.134.177 +trace

; <<>> DiG 9.4.2 <<>> -x 63.254.134.177 +trace
;; global options:  printcmd
.                       54948   IN      NS      j.root-servers.net.
.                       54948   IN      NS      c.root-servers.net.
.                       54948   IN      NS      k.root-servers.net.
.                       54948   IN      NS      b.root-servers.net.
.                       54948   IN      NS      l.root-servers.net.
.                       54948   IN      NS      h.root-servers.net.
.                       54948   IN      NS      f.root-servers.net.
.                       54948   IN      NS      m.root-servers.net.
.                       54948   IN      NS      e.root-servers.net.
.                       54948   IN      NS      d.root-servers.net.
.                       54948   IN      NS      a.root-servers.net.
.                       54948   IN      NS      g.root-servers.net.
.                       54948   IN      NS      i.root-servers.net.
;; Received 449 bytes from 172.30.111.254#53(172.30.111.254) in 1 ms

63.in-addr.arpa.        86400   IN      NS      X.ARIN.NET.
63.in-addr.arpa.        86400   IN      NS      Y.ARIN.NET.
63.in-addr.arpa.        86400   IN      NS      INDIGO.ARIN.NET.
63.in-addr.arpa.        86400   IN      NS      DILL.ARIN.NET.
63.in-addr.arpa.        86400   IN      NS      HENNA.ARIN.NET.
63.in-addr.arpa.        86400   IN      NS      Z.ARIN.NET.
63.in-addr.arpa.        86400   IN      NS      BASIL.ARIN.NET.
;; Received 181 bytes from 192.36.148.17#53(i.root-servers.net) in 60 ms

254.63.in-addr.arpa.    86400   IN      NS      NS2.MCLEODUSA.NET.
254.63.in-addr.arpa.    86400   IN      NS      NS1.MCLEODUSA.NET.
254.63.in-addr.arpa.    86400   IN      NS      NS3.MCLEODUSA.NET.
;; Received 112 bytes from 192.26.92.32#53(HENNA.ARIN.NET) in 41 ms

177.134.254.63.in-addr.arpa. 7200 IN    NS      ns2.cyzap.net.
177.134.254.63.in-addr.arpa. 7200 IN    NS      ns1.cyzap.net.
;; Received 90 bytes from 209.253.113.19#53(NS3.MCLEODUSA.NET) in 17 ms

177.134.254.63.in-addr.arpa. 3600 IN    CNAME  
177.176-28.134.254.63.in-addr.arpa.
177.176-28.134.254.63.in-addr.arpa. 16 IN PTR   testnew177.cyzap.net.
;; Received 104 bytes from 172.30.111.3#53(ns1.cyzap.net) in 0 ms

===================================================================
Why did the simple dig (without trace or specifying ns1.cyzap.net)  not
return the PTR record?
Also, if I do  dig @ns1.cyzap.net -x 63.254.134.177 and then dig -x
63.254.134.177 +trace , it will not give the PTR record if it traces to
ns2.cyzap.net. If I do,  dig @ns2.cyzap.net -x 63.254.134.177 and then
dig -x 63.254.134.177 +trace, it will not give PTR record if it traces
to ns1.cyzap.net. That is why sometimes I am getting PTR from trace
option and sometimes not. Something is broken here.


Thank you,
Raj


Kevin Darcy wrote:
> Raj Adhikari wrote:
>> Thanks Chris for the reply.
>> Actually, let me put my question the other way.
>> How can one delegate the classless subnet to other DNS?
>> Actually, one of our ISP could not delegate classless subnet to our
>> server ns1.cyzap.net. I am trying to help them in delegating the
>> classless subnet to us. So this scenario is simulating our ISP and us. I
>> was just testing with one of our other subnets checking if delegation
>> will work. Unfortunately, we both are using windows DNS. Windows just
>> have RFC 2317 way on configuring the delegation on it KB article using
>> CNAME, which I think has lots of problems. But I am following this BIND
>> way for delegation. I think, in windows the DNS configuration is more or
>> less similar to BIND.
>>   
> There is no "BIND way" versus "Windows way". For a range smaller than
> /24 you either need to host all the records in the /24 zone, delegate
> each entry individually (as /32 zones), or use CNAMEs. This is
> determined by the protocol, regardless of whether you're using
> Microsoft DNS, BIND or any other implementation.
>
> Note that many thousands (tens of thouands? hundreds of thousands?) or
> organizations use RFC 2317 for their reverse DNS without issues. So,
> on what do you base your assessment of this approach as having "lots
> of problems"? The folks who published RFC 2317 actually know what
> they're talking about. People complaining on forums about having
> botched their RFC 2317 configs, probably *don't*.
>> In this scenario, lets say ns1.cyzap.net is my ISP and
>> ns1.monetreesystems.com is us. ns1.cyzap.net owns 63.254.134.0/24 and
>> ns1.moneytreesystems.com take a subnet 134.224/28 from them. So isn't
>> there a way for ns1.cyzap.net to delegate the subnet to
>> ns1.moneytreesystems.com? 
> The /24 is delegated to ns1.cyzap.net. Zone delegation is on octet
> boundaries. So the next available boundary for delegation would be
> /32, i.e. delegating each of the 16 usable addresses (or perhaps just
> the 14 usable addresses) individually.
>> Do ns1.cyzap.net again have to talk to their
>> upper ISP to delegate directly to us? 
> No, that doesn't help. What would the /16 nameservers delegate?
> They've already delegated 134.254.63.in-addr.arpa, there's nothing
> more you can expect of them.
>
> - Kevin
>> Chris Hills wrote:
>>  
>>> On 10/11/09 18:25, Raj Adhikari wrote:
>>>    
>>>> Now I can do a dig for an hour or so. But again I run into same
>>>> problem.
>>>> It wont return PTR record unless I explicitly do dig on ns1.cyzap.net.
>>>> Also, the last did showing ns1.cyzap.net as Authority NS for this IP.
>>>> But trace showing ns1.moneytreesystems.com as final sender.
>>>>
>>>> Could someone shed a light on this?
>>>>       
>>> 254.63.in-addr.arpa.    86400   IN      NS      NS3.MCLEODUSA.NET.
>>> 254.63.in-addr.arpa.    86400   IN      NS      NS1.MCLEODUSA.NET.
>>> 254.63.in-addr.arpa.    86400   IN      NS      NS2.MCLEODUSA.NET.
>>> ;; Received 112 bytes from 192.42.93.32#53(y.arin.net) in 173 ms
>>>
>>> 228.134.254.63.in-addr.arpa. 7200 IN    NS      ns1.cyzap.net.
>>> 228.134.254.63.in-addr.arpa. 7200 IN    NS      ns2.cyzap.net.
>>> ;; Received 90 bytes from 209.253.113.19#53(NS3.MCLEODUSA.NET) in
>>> 159 ms
>>>
>>> 228.134.254.63.in-addr.arpa. 3600 IN    NS     
>>> ns2.moneytreesystems.com.
>>> 228.134.254.63.in-addr.arpa. 3600 IN    NS     
>>> ns1.moneytreesystems.com.
>>> ;; BAD (HORIZONTAL) REFERRAL
>>> ;; Received 160 bytes from 64.253.181.53#53(ns2.cyzap.net) in 167 ms
>>>
>>> You should not chain a delegation in this manner. Either make the
>>> servers ns1.cyzap.net. and ns2.cyzap.net. authoritative for
>>> 228.134.254.63.in-addr.arpa. or have your ISP change the NS records to
>>> point directly to ns1.moneytreesystems.com. and
>>> ns2.moneytreesystems.com. The cyzap servers do not respond with the
>>> authority bit set ("aa" in dig).
>>>
>>> Regards,
>>>
>>> Chris
>>>
>>> _______________________________________________
>>> bind-users mailing list
>>> bind-users at lists.isc.org
>>> https://lists.isc.org/mailman/listinfo/bind-users
>>>     
>>
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>>   
>
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