changes passwords for user accounts. A normal user may only change the password for his/her own account, while the super user may change the password for any account.
The user is first prompted for his/her old password, if one is present. This password is then encrypted and compared against the stored password. The user has only one chance to enter the correct password. The super user is permitted to bypass this step so that forgotten passwords may be changed.
After the password has been entered, password aging information is checked to see if the user is permitted to change the password at this time. If not,
The user is then prompted twice for a replacement password. The second entry is compared against the first and both are required to match in order for the password to be changed.
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Then, the password is tested for complexity. As a general guideline, passwords should consist of 6 to 8 characters including one or more characters from each of the following sets:
System encryption method is based on the NBS DES algorithm and is very secure. The size of the key space depends upon the randomness of the password which is selected.
Compromises in password security normally result from careless password selection or handling. For this reason, you should not select a password which appears in a dictionary or which must be written down. The password should also not be a proper name, your license number, birth date, or street address. Any of these may be used as guesses to violate system security.
Your password must be easily remembered so that you will not be forced to write it on a piece of paper. This can be accomplished by appending two small words together and separating each with a special character or digit. For example, Pass%word.
Other methods of construction involve selecting an easily remembered phrase from literature and selecting the first or last letter from each word. An example of this is:
You may be reasonably sure few crackers will have included this in their dictionaries. You should, however, select your own methods for constructing passwords and not rely exclusively on the methods given here.
This option is used to disable an account after the password has been expired for a number of days. After a user account has had an expired password for
\fIINACTIVE\fR
days, the user may no longer sign on to the account.
Indicate change password should be performed only for expired authentication tokens (passwords). The user wishes to keep their non\-expired tokens as before.
Display account status information. The status information consists of 7 fields. The first field is the user's login name. The second field indicates if the user account is locked (L), has no password (NP), or has a usable password (P). The third field gives the date of the last password change. The next four fields are the minimum age, maximum age, warning period, and inactivity period for the password. These ages are expressed in days.
Not all options may be supported. Password complexity checking may vary from site to site. The user is urged to select a password as complex as he or she feels comfortable with. Users may not be able to change their password on a system if NIS is enabled and they are not logged into the NIS server.