Just realized that one of my domain controllers, that is also a global catalog, is not listed in the reverse lookup zone with a PTR record, it is not there. The other two domain controllers are there.

There is a valid Host A record though in the forward lookup zone of DNS in Active Directory Zone for it though. Is there a way to force the PTR record? Is this something that i might have to manually do to create the record?

All three domain controllers are Server 2003.

Update, i tried using nslookup on the main domain controller, if i change the server for nslookup to another domain controller and then type in the word server and hit return i get non-existent domain? Am i reading nslookup the wrong way when it comes to the word server, i thought it would just return the value of the DNS server that nslookup is using for the queries.

Update 2: If i go to a workstation and change the tcp/ip settings for dns1 to point to the domain controller that does not have the PTR record and do an nslookup this is the error i get

nslookup * Can't find server name for address Non-existent domain * Default servers are not available Default Server: UnKnown Address:

i am assuming i get this error since there is no PTR record? all other lookups with this Domain Controller resolve fine, such as google.com and other internal domain computer names. Will this cause issues for users logging in if i change the DHCP scope and use this problematic Domain Controller for their DNS1 entry?

Update 3: i restarted the server, i realized it not been restarted since a while ago when i did the dcpromo, when i logged back in and checked the Reverse Lookup Zone for all 3 Domain Controllers the PTR records was no there and the error above about non-existent domain does not come up when you do an nslookup it just goes right to the comman line for nslookup. Thanks again.

  • Running 'server <hostaddr>' command in nslookup changes the dns server that queries are run against. Typing server by itself initiates a dns search for host 'server' – uSlackr Sep 20 '11 at 12:42
  • yes you are right i did realize that just typing server means look that name up and it fails. thanks. – dasko Sep 20 '11 at 12:48
  • i updated what fixed the issue in the main question, Update 3 – dasko Sep 20 '11 at 12:57
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    rDNS zones and PTR records aren't required for the operation of AD or your DC's or AD related DNS. In fact, I'm hard pressed to see where rDNS zones and PTR records have any usefulness internally. – joeqwerty Sep 20 '11 at 13:28

If the entry is missing, running ipconfig /registerdns on the server missing entries should repopulate DNS.


Check that dynamic DNS registration for PTR records isn't disabled for some reason.

In a command prompt:

reg query HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters /v DisableReverseAddressRegistrations

If the value returned is 0x0 or ERROR: The system was unable to find the specified registry key or value. then this is not the problem in your case.

If the value returned is 0x1 then your server won't try to automatically register its PTR records. To fix it, issue the following command:

reg add HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters /v DisableReverseAddressRegistrations /t REG_DWORD /d 0

More info: MSKB 246804: How to enable or disable DNS updates in Windows 2000 and in Windows Server 2003.

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