Setting the date and time is very important for a system administrator. Why? Because if you find something inappropriate or possibly problematic in your log files (e.g., repeated unsuccessful login attempts from a specific location), you want to be able to accurately cross-reference your log files with the log files of your colleagues at the other location. That can happen only if the time on both hosts is pretty close to accurate.
To Set the Time with ntpdate:
Code Listing 16.7. Setting the date (and making sure it stays up-to-date) is an important root user responsibility.