Changing your password
To change your password, use the passwd utility. You're prompted for your current password and then for a new one. You have to repeat the new password to guard against typographical errors.
Depending on the password rules that the system administrator has set, passwd may require that you enter a password of a certain length or one that contains certain elements (such as a combination of letters, numbers, and punctuation). If the password you select doesn't meet the criteria, passwd asks you to choose another.
If other users can access your system (e.g., it's connected to the Internet, has a dial-in modem, or is physically accessible by others), be sure to choose a password that will secure your account from unauthorized use. You should choose passwords that:
- are more than 5 characters long
- consist of multiple words or numbers and include punctuation or white space
- you haven't used on other systems (many systems, and websites in particular, don't store and communicate passwords in a hashed form; this lets people who gain access to those systems see your password in plain text)
- incorporate both uppercase and lowercase letters
- don't contain words, phrases, or numbers that other people can guess (e.g., avoid the names of family members and pets, license plate numbers, and birthdays)
For more information on system security, see Securing Your System.