Question about DNS

[rodentcentre]

I really know little to nothing about DNS so I was perusing DNS on one our servers and saw some wierd entries in my Forward Lookup Zones:

friend-cards.net
gator.com
icq.com
kazaa.com
limewire.com
morpheus.com

Now I know what all of those are from a client perspective but what in the world would they be doing as entries into DNS?? Is DNS a dense enough subject to require learning all about its ins and outs?? If so can you recommend a good book?? Thanks.

 

[technome]

Your referring to the cached lookup...
They are in there because they are cached dns results, someone or some program accessed these sites.

Good book...
Mastering Windows 2000 (or 2003) server by Mark Minasi, Sybex
The DNS section ( a couple hundred pages) is one of the most easily understandable explainations of DNS I have run across, though DNS is not the most easy subject. You should have a decent understanding of DNS, especially if your have an Active Directory network. If your a consultant you need to know it well, otherwise you need to understand the basic concepts, and have references. Understand "split brain" DNS and other security concepts