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nugentglFlag for United States of America

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Wireless and multiple subnet problem

I am having a DNS issue with my laptops.  I have 4 local subnets that my laptop users will periodically connect to during the course of the day.  When they connect to a new subnet, they get a new IP and then DNS is updated.  So for one laptop, DNS could show 4 separate IP addresses.  This causes problems with some applications, for example, our ERP system will work just fine in their original subnet (either wireless or wired), but when they go to another subnet, they get errors saying the server is not available.  I'm guessing because it is going after the wrong DNS entry for the client.  Any suggestions as to how to configure DHCP and DNS to minimize this problem?

I am running a Win2k3 AD with DNS active directory enabled and all the clients are XP Pro.

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iCoreKC
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And I wanted to add this one as it has some different information for a manual process if desired.

http://www.myitforum.com/articles/16/view.asp?id=6287
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Thanks for the info.  However, I am not following your setup.  Where do I enable those settings?
Right click over your Zone server in your DNS Administration applet and go to properties.  You will see an Aging button.  Set the properties here.
Make sure you tick the Scavenge Stale Resource Records box and then I would set the No Refresh Interval to 1 Day and the Refresh Interval to 2 Days or under, but don't go below 1 day on either of the settings as this can cause issues with auto generated domain records.  

In an normal environment I would set my DHCP leases to 3 days and then No Refresh Interval to 1 Day and the Refresh Interval to 2 Days.  This has worked for us for years and we do not have any problems with duplicate A records.  In your situation you may need to experiment because it sounds like some of your users log into several subnets per day.  If you set your DHCP scope to 1 day and then the Scavenging as described you may see some issues, but I would try it and watch your DNS records to see what is happening.

With a DHCP lease of 1 day or even less in your environment, I would try a 1 day No Refresh Interval and 1 day 6 hour Refresh Interval.