14.5.
Password Maintenance
How often should I change my password? What
should my password look like?
For security reasons, it is a good idea to change your root and
user passwords regularly. Experts vary on how often this change
should occur, but most agree that passwords should be changed
multiple times each year.
Passwords should not be based on a dictionary word should be at
least six characters, and should include: both lower-case and
upper-case letters, at least one number, and at least one
punctuation mark. Don't write your password down or store it in an
unencrypted file. Don't give your password to anyone.
User passwords can be set to automatically expire after a
certain amount of time. Refer to the Red Hat Enterprise Linux
System Administration Guide for more information.
