The event log is an administrator's best friend when it comes to detecting and troubleshooting problems. Although some of the error messages are not quite as clear as they could be, Microsoft's Knowledgebase and eventid.net are valuable resources that shed light on the more cryptic messages.

Windows server 2003 allows you to audit and log a multitude of activities within the AD, from access to files, to access to objects. Your organization may require some of these, either by law or by policy. In that case, storing them is problematic, as you have to back them up on each server. On top of that, you have to check each server for issues and logs, which is a big pain if you have more than ten DCs, especially when they are distributed all over the world with people working at different hours.

Having a central log collector provides the administrators with a very valuable tool—the ability to check all the servers' events from a central point. There are many commercial, and pricey...