Reverse lookup zone resolution in conditional forwarder RRS feed

  • General discussion

  • Scenario1

    I was involved in a discussion whether we can get the reverse lookup zone name resolution, if I'm using conditional forwarder.

    Conditional forwarder: Host to name resolution will work, but will It also able to resolve IP to host name for the resources in other domain in dns using nslookup, if yes, how.

    If not, how can we make it work to resolve IP to host to other domain from my own domain using conditional forwarder, considering if I have similar private IP range configured into my own reverse lookup zone as another domain, how dns will resolve name from if I use IP into NSlookup for another domain.


    Another scenario:

    I have my own domain XYZ.com & another domain named abc.com with authoritative DNS server IP for ABC domain) configured as forwarder in my domain for ABC domain name resolution from xyz, I have also existing 192.168.1.x configured as reverse lookup zone configured for my internal domain name resolution, the question is if I do nslookup using IP 192.168.1.x will it give nslookup for my own domain or another domain


    I don't have lab to test, so request if anyone have tested or can share something on it.

    • Changed type Awinish Tuesday, April 12, 2011 8:39 AM I don't think answer can be yes or no.
    Friday, April 8, 2011 9:01 AM

All replies

  • Of course conditional forwarding works for reverse lookup also. It's all about zone , if you name it 1.168.192.in-addr.arpa then you will forward all requests for 192.168.1.x

    As for the second scenario , if you're forwarding only abc.com zone , you won't be forwarding reverse lookups via it. Forwarding will work if you use the name above

    Sunday, April 10, 2011 9:28 AM
  • Alexander, thanks for your post.

    I don't have lab to test, but as i have read from various forums/blogs also discussed with some greats one is Joe Richards, reverse lookup will not work for forwarder/conditional forwarder. Joe too said it will not work, but he was not sure & asked for testing it.

    Consider, i try to resolve the another domain using 192.168.1.x in nslookup where i got same subnet configured in reverse lookup zone in my own domain, technically it  query should not look for any forwarder or conditional forwarder since local subnet & zone already exists in my domain. Forwarder/conditional forwarders are only used when query can't be resolved locally means using zones & subnet configured.

    I believe someone can confirm testing in their lab.



    Awinish Vishwakarma| MY Blog

    Disclaimer: This posting is provided AS-IS with no warranties or guarantees and confers no rights.

    Sunday, April 10, 2011 11:20 AM
  • why it shouldn't work ? conditional forwarder doesn't change anything in the basic structure of DNS (working based on zones) only the logic how a lookup is serverd.

     as for the second part , the request won't forward because you already have that zone

    I'll be glad to be proven wrong

    Sunday, April 10, 2011 12:17 PM
  • I didn't mean you are right or wrong, but i wish someone test in their lab & can confirm me.



    Awinish Vishwakarma| MY Blog

    Disclaimer: This posting is provided AS-IS with no warranties or guarantees and confers no rights.

    Sunday, April 10, 2011 6:26 PM
  • Awinish,

    If you need to forward a reverse lookup request “conditionality”, you need to create a conditional forwarder for your reverse lookup zone (X.X.X.in-addr.arpa).  


    Santhosh Sivarajan | MCTS, MCSE (W2K3/W2K/NT4), MCSA (W2K3/W2K/MSG), CCNA, Network+ Houston, TX

    Blogs - http://blogs.sivarajan.com/
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    Twitter: @santhosh_sivara - http://twitter.com/santhosh_sivara

    This posting is provided AS IS with no warranties, and confers no rights.
    Monday, April 11, 2011 12:57 AM
  • Thanks Santhosh, i too read somewhere on this but do u got lab to test this.



    Awinish Vishwakarma| MY Blog

    Disclaimer: This posting is provided AS-IS with no warranties or guarantees and confers no rights.

    Monday, April 11, 2011 5:12 AM
  • Hi,

    i have tested with creating reverse conditional forwarder like 1.168.192.in-addr.arpa but it gives the error as "Zone configuration problem occurred"

    if i create CF adding .com ( 1.168.192.in-addr.arpa.com ) then am able to create conditional forwarder but the IP resoltion still not working.

    there is only one work around i found for IP resolution is to create PTR record in reverse lookup zone.

    please suggest..


    Sadheesh S


    Thursday, October 11, 2012 11:20 AM
  • Hi,

    I encoutered the same issue recently, I was able to do the conditional forwarder like 1.168.192.in-addr.arpa, but by doing this as prerequisite, create a new reverse zone 192.in-addr.arpa, then at the reverse zone level 192.in-addr.arpa, create a delegation for 1.168.192.in-addr.arpa that target NS Server one of your DNS server. Now your able able to create conditional forwader 1.168.192.in-addr.arpa without Zone configuration problem.



    Wednesday, November 28, 2012 3:21 PM
  • Hello Frederic:

    A belated thank you for this correct response.  I've tested this and it actually works.

    The step of creating a conditional forwarder is not necessary if the delegations are properly created and populated with the NS records in the partner forest.

    • Edited by RS of ITS Monday, August 3, 2020 9:22 PM Clarification
    Monday, August 3, 2020 6:44 PM