Protection against system intrusion. Once your system has been compromised you may never have good reason for trusting that system again. You need to follow security procedures from the moment a system comes out of the box, especially before you connect it to a network. Put passwords on every account. Use only good passwords.
Good passwords are at least eight letters and digits long.
Install security-related operating system patches as soon as they become available. Perform regular monitoring of your system s use so that you will know when unusual usage occurs. Your system s accounting log is an invaluable tool. Take regular backups. Assuming that you know when an intrusion has occurred, restore your entire system from before the intrusion to ensure nothing has been left behind.