DNS Scavenging Turned On....Or Is It?

I have had lots of issues with Windows Server DNS configurations, and a good 90% of those issues circle around scavenging.

What is scavenging you ask? It is the process of removing old invalid records from the DNS index so that (especially in DHCP scopes) computer names are correctly reflected in name resolution and more commonly for an end user, the Networked Computers window.

I believe to finally have solved the problem with a final karate chop to the Windows Server 2008 R2 (in this case) GUI. I believe the graphical interface for most Microsoft products is great, but I will add DNS management to the list of not so great products.

As hard as I tried scavenging was not enabled on my server, I had it setup on each zone as well as the host (even though it was not tied to Active Directory and therefor the option shouldn't matter) but yet in the Best Practices results it always stated it was off. I was caught by good surprise when I had seen this hoping that finding a fix should solve my issues once and for all (since I know a certain users laptop does not have 5 network connections so should not be listed under as many IP addresses at once..). I followed some basic command line garble and after inputting it into the console finally had the results I was looking for (though the next week of testing will tell me if it REALLY works now). Follow the commands below on your DNS server to truly enable scavenging.

To check your setup and see if it is enabled type in : dnscmd <DNSSERVERNAME> /Info

If ScavengingInterval is set to something other than 0 it is actually enabled, if set to 0 work through the following commands.

1. Open a Command Prompt session
2. Type in the following : dnscmd <DNSSERVERNAME> /Config /ScavengingInterval 168
3. Hit Enter
4. Verify by typing in: dnscmd <DNSSERVERNAME> /Info

The 168 hour value is a default that should be assigned to scavenging (mine was set to 0 and therefor disabled)