Server 2003 SP2 is available. You should start there.
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Browse All TopicsSystem is Windows Server 2003 Standard SP1 running DNS services, fully patched and current with all Windows updates. This machine is a secondary DNS server. After being in service nearly 2 years, jsut 2 weeks ago this server suddenly began using excessivly high amounts of memory for the dns.exe process. By high, I mean that after restarting the DNS service, it begins a near-linear increase (no spikes, just fairly constant slope upward) in memory use, easily exceeding 1.25 GB of memory after 4 or 5 days. I restart the process, and the even repeats itself. Until now, memory use was nearly a flat line.
I have completely uninstalled the DNS service, and re-installed.
This machine serves only a few hundred zones (stored in zone files & registry, NOT Active Directory, is stand-alone server and not a member of any AD domain) and answers ONLY for its own zones (recursion is disabled, root hints file has been removed).
I have repeatedly googled and searched the MS KB for answers on high memory utilization for the DNS service, but have come up with noting relevant.
Anyone seen this problem, or have a reference to a known issue/fix?
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I have the same problem too. It started about a month ago and is seen only on secondary dns servers. Problem started at the same time on 3 different machines which are running as secondary dns. Other primary dns servers have no problem. My servers are all updated, all service packs, updates etc., but the problem continues and no recent windows update solved it yet. I think that this issue might be related to an update, because the problem started at the same time on different servers. As windows update is done automatically, an update might have affected all servers at the same time.
Because I couldn't find a solution yet, I scheduled 'dns service restarts' with the command "dnscmd.exe . /restart". As the service restarts itself periodically with this command, the memory consumption is kept low, but of course an exact solution must be found. I hope a future update of windows would solve this problem.
evrenuyanik, thanks for the info. I'm glad someone else has the same symptoms I do, starting around the same time as the Windows updates came out. The same day as my original post, I did the same thing of having a script fire around 3 a.m. to restart the service. Hopefully enough people will report it, that MS will diagnose and put out a hotfix or Windows update for it.
On a server of ours, we have about 2000 zones, that servers memory is increasing very fast, I set up that server so that it restarts the dns service every 1 hour. Because the restart process takes place in just a few seconds, there is no disadvantage of restarting it frequently; so restarting it every 1 hour keeps memory consumption low. Before setting up these restarts, the server was slowing done distinctly; after setting up scheduling for restarts, the speed of the machine has increased.
Yes they know about it. I have sent a few hundred emails over the past 2 weeks with a support engineer from Microsoft trying to debug the issue.
My experience:
We had our DNS servers patched with this patch on Jan 4th. One week later we started to get zone that expired and the DNS service started to crash on the servers. After support from Microsoft told us that the process had a memory leak that was found after release. We were trying to debug the problem. In addition to the whole issue we had netowrk problem which were causing even bigger dns issues.
So in short the symptoms could be:
- DNS.exe process uses a lot of memory (It can easily go over 100mb)
- DNS service stops responding - it looks like it works, but does not transfer zones or forward queries.
At the moment the only thing that can be done is restart the DNS to clear the memory.
Microsoft will release a patch for the issue in the future, but do not have a release date yet.
And no this is not public knowledge until now....
If anyone would like more detailed info please contact me off line at maishsk--@ gmail.com (remove the --)
Seeing that several people have asked me offline what the solution to this one was, I will post what I know here.
At the moment the only thing I fount that brought down the memory usage for the DNS services was to remove KB941672
Machine with patch - version of dns.exe - 5.2.3790.3027
After patched removed
version of dns.exe - 5.2.3790.2915
I guess we will all have to wait for Microsoft to get their act together and fix this patch up properly
Thanks for the update. It's disappointing that MS can't fix a simple memory leak in this many months. They know it relates to KB941672, and they know what code changes were written into that release, so it doesn't seem like a monumental task to back track their steps and see what demon was compiled in.
(Disclaimer: I am not a programmer.)
Pls try this
http://support.microsoft.c
I'm struggling to get the hotfix from Microsoft. The DNS server is running Server 2003 Standard at SP1. The rep responded back saying the hotfix is not available for this edition, even though the hotfix prerequisites clearly state Server 2003 at SP1 or SP2. Their support seems to be sliding downhill in recent years.
In the message was a link to provide feedback to the manager, along with the manager's name and employee's name. So I used it... and I replied back to the employee making the decline, with a quote from the KB article. A few hours later, the link for hotfix download arrived. :)
I installed it late yesterday, and so far memory utilization has remained flat for more than 12 hours (a very good sign). Without the fix, after 12 hours, memory utilization would be up 200-300 MB based on the trends of the past 30 days. I'll give it a few days to be sure before closing this request, but at the moment it looks like maishsk hit the nail on the head, and sivanov provided the correct link to the fix.
ok i got a bird that tells me that the fix works in 99.9% of the cases - reazon for failure usually are - nor restarting the service after updates, sometimes its needed to reboot the server - i've also read 0.01 % issues which for the moment are solved by workaround with replasing the dns.exe and dll with version previous that KB941672, but must be aware that every MS update will try to replace them with KB941672.
OK FINALY AGAIN http://support.microsoft.c
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by: from_expPosted on 2007-11-29 at 13:23:14ID: 20377451
If you haven't done any changes(new updates, new zones, new firewall rules etc) recently, nehavior of dns process is a result, not a root of a problem.
try to sniff traffic with wireshark from the dns machine with dns process running.