When DNS scavenging isn’t turned on old DNS records will stay populated in DNS, cluttering up your network routing. You’ll end up with PC’s listed multiple times at different IP addresses. Depending on your network setup the same thing could happen to servers. This means that traffic will be taking all sorts of paths to get to it’s destination – some of the correct and some of them incorrect.
We have a motto: It’s always DNS. So check your DNS scavenging settings. Because one of the often missed sets is to enable it.
Here’s how you do it:
Open DNS Manager. Right click on the DNS server and select properties. Move to the Advanced tab. At the bottom of the page check the box to enable scavenging. I usually leave the other settings at default but you can modify as needed. This is only half of the setup you need to perform. Checking this box will actually not result in any scavenging taking place.
The next step is to enable scavenging on the forward lookup zones you want scavenged. To do this, expand Forward Lookup Zones and right click on the zone that you wish to have scavenged. Generally this will be the zone where your PC’s reside. Choose Properties from the menu. This time stay on the General tab and press the Aging button.
Now that you’ve enable scavenging AND selected the DNS zone to be scavenged, scavenging will begin to happen.
If you server has been around for a while without scavenging turned on, you might want to perform a manual clean up. To do this sort the records in the zone by Timestamp and delete any records that are more than a couple of weeks old. Then let your newly configured scavenging setting take it from there.