Ubuntu Unleashed 2013 Edition: Covering 12.10 and 13.04, Eighth Edition

Passwords and Physical Security

The next step toward better security is to use secure passwords on your network and ensure that users use them as well. For somewhat more physical security, you can force the use of a password with the GRUB bootloader, remove bootable devices such as floppy and CD-ROM drives, or configure a network-booting server for Ubuntu.

Also keep in mind that some studies show that as many as 90 percent of network break-ins are done by current or former employees. If a person no longer requires access to your network, lock out access or, even better, remove the account immediately. A good security policy also dictates that any data associated with the account first be backed up and retained for a set period of time to ensure ...