Solved

DNS Scavenging - Stale records not deleted from forward lookup zone

Posted on 2014-07-24
2
5,024 Views
Last Modified: 2014-07-24
Hello,

I am trying to implement DNS scavenging in my Active Directory integrated DNS environment, but I have a weird situation occurring.  All stale PTR records are being scavenged properly from the reverse lookup zones, but the stale A records in my primary forward lookup zone stubbornly remain.  My environment contains 3 DNS servers- 2 Windows Server 2003 Standard Edition SP2 DC's and a single Windows Server 2008 R2 SP1 DC.

Here is what I have done so far:

1.  Enabled aging/scavenging on all of the zones I wish to scavenge on the DNS servers
2.  I watched over the next several weeks to see how the timestamps were replicated around the DC's and made sure that all of my critical systems were updating as expected so that they would not be accidentally deleted.
3.  The zones in question were eligible to be scavenged several weeks ago according to DNS
4.  I proceeded to enable scavenging on the Windows Server 2008 R2 SP1 DC/DNS server and set it to scanvenge the stale resource at the default interval of 7 days
5.  In order to make an immediate scavenging pass, I manually initiated a scavenging operation on the DC mentioned in step 4 above.
6.  The results were that all of the stale records in the multiple reverse zones were immediately scavenged as expected.  However, all of the stale resource records in the forward lookup zone remain and will not be removed no matter where I run the manual scavenge from.
7. I checked the security tab on the records in both types of zones and everything is identical

My question here is - what am I missing? I followed this article as exactly as possible, but perhaps I have overlooked some nuance:

http://blogs.technet.com/b/networking/archive/2008/03/19/don-t-be-afraid-of-dns-scavenging-just-be-patient.aspx

All of the stale A records are set to be scavenged when they become stale (checkbox on the record itself) and all of them are very VERY old 7/1/2009 for example.  Scavenging is enabled in all three places - the DNS server, the zone in question, and the individual A record.

Perhaps my best bet is just to manually delete all of the old A records from the forward lookup zone and then watch the behavior with all newly created dynamic A records moving forward?  Could it be something with the mix of 2003 and 2008 R2 DNS servers?

Any ideas? Please don't ask if I have enabled scavenging on the DNS server as well as the individual zones.  That is the canned answer that appears over and over on technet and google as a response to this problem.  I came to Experts Exchange with this issue for a reason! ;-)

Thanks in advance,

Jon
0
Comment
Question by:KPI1
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
2 Comments
 
LVL 37

Accepted Solution

by:
Mahesh earned 500 total points
ID: 40217791
1st of scavenging needs to be set only on domain dns zones (ex: Contoso.com) and all ad integrated reverse lookup zones
Also I hope you have set scavenging on single server only.

You need to reset scavenging 1st by running below command in elevated command prompt
dnscmd /zoneresetscavengeservers contoso.com         ------ Replace Contoso.com with your domain name, this command will reset scavenging and clear if you have set different servers for scavenging in past

Then set the Scavenging server for a zone, run the command:
dnscmd /zoneresetscavengeservers contoso.com <Ip of the current DNS Server>

Check if scavenging settings are remain unchanged on zone level and server level

Then check if it works properly
Check below article for more details
http://support.microsoft.com/kb/2791165

One another workaround I can see is to delete all very old record manually from dns zones because sometimes I found that no matter what you try, scavenging process do not delete some old records, however once you deleted those very old records, the problem won't occur again specially when scavenging is now in place.
0
 

Author Comment

by:KPI1
ID: 40218127
Thanks Mahesh,

Yes I have it configured to scavenge on only a single server.  I will try the /zoneresetscavengerservers command and see if that fixes it, but I don't see any settings in /zoneinfo for the domain to indicate that an old server is configured for scavenging like the KB article referenced in you post mentions.

If that doesn't work, I will manually delete the old records since my zone is only a couple of hundred A records.  Then I will see if the problem persists.

Thank you for your assistance,

Jon
0

Featured Post

DevOps Toolchain Recommendations

Read this Gartner Research Note and discover how your IT organization can automate and optimize DevOps processes using a toolchain architecture.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

ADCs have gained traction within the last decade, largely due to increased demand for legacy load balancing appliances to handle more advanced application delivery requirements and improve application performance.
While rebooting windows server 2003 server , it's showing "active directory rebuilding indices please wait" at startup. It took a little while for this process to complete and once we logged on not all the services were started so another reboot is …
This tutorial will walk an individual through locating and launching the BEUtility application to properly change the service account username and\or password in situation where it may be necessary or where the password has been inadvertently change…
This tutorial will walk an individual through the process of transferring the five major, necessary Active Directory Roles, commonly referred to as the FSMO roles to another domain controller. Log onto the new domain controller with a user account t…

738 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question