Man Pwck en anglais
PWCK(8)                   System Management Commands                   PWCK(8)



 

NAME


       pwck - verify integrity of password files

 

SYNOPSIS


       pwck [-q] [-s] [passwd [ shadow ]]

       pwck [-q] [-r] [passwd shadow]

 

DESCRIPTION






       The pwck command verifies the integrity of the system authentication
       information. All entries in the /etc/passwd and /etc/shadow are checked
       to see that the entry has the proper format and valid data in each
       field. The user is prompted to delete entries that are improperly
       formatted or which have other uncorrectable errors.

       Checks are made to verify that each entry has:

       o   the correct number of fields

       o   a unique user name

       o   a valid user and group identifier

       o   a valid primary group

       o   a valid home directory

       o   a valid login shell

       The checks for correct number of fields and unique user name are fatal.
       If the entry has the wrong number of fields, the user will be prompted
       to delete the entire line. If the user does not answer affirmatively,
       all further checks are bypassed. An entry with a duplicated user name
       is prompted for deletion, but the remaining checks will still be made.
       All other errors are warning and the user is encouraged to run the
       usermod command to correct the error.

       The commands which operate on the /etc/passwd file are not able to
       alter corrupted or duplicated entries.  pwck should be used in those
       circumstances to remove the offending entry.

 

OPTIONS


       The options which apply to the pwck command are:

       -q
           Report errors only. The warnings which do not require any action
           from the user won't be displayed.

       -r
           Execute the pwck command in read-only mode.

       -s
           Sort entries in /etc/passwd and /etc/shadow by UID.

       By default, pwck operates on the files /etc/passwd and /etc/shadow. The
       user may select alternate files with the passwd and shadow parameters.

 

CONFIGURATION


       The following configuration variables in /etc/login.defs change the
       behavior of this tool:

       PASS_MAX_DAYS (number)
           The maximum number of days a password may be used. If the password
           is older than this, a password change will be forced. If not
           specified, -1 will be assumed (which disables the restriction).

       PASS_MIN_DAYS (number)
           The minimum number of days allowed between password changes. Any
           password changes attempted sooner than this will be rejected. If
           not specified, -1 will be assumed (which disables the restriction).

       PASS_WARN_AGE (number)
           The number of days warning given before a password expires. A zero
           means warning is given only upon the day of expiration, a negative
           value means no warning is given. If not specified, no warning will
           be provided.

 

FILES


       /etc/group
           Group account information.

       /etc/passwd
           User account information.

       /etc/shadow
           Secure user account information.

 

SEE ALSO


       group(5), passwd(5), shadow(5), usermod(8).

 

EXIT VALUES


       The pwck command exits with the following values:

       0
           success

       1
           invalid command syntax

       2
           one or more bad password entries

       3
           can't open password files

       4
           can't lock password files

       5
           can't update password files



System Management Commands        12/06/2009                           PWCK(8)