Using pwck to Check the Password File

Using pwck to Check the Password File

From time to time, you should run the pwck(1M) utility to scan the password file. This program reads the file and checks each entry for completeness and notes any inconsistencies. The password checks include validation of:

the number of fields in each entry
the login name
the user ID number
the group ID number
the login directory
the executed program

The default password file to be checked is /etc/passwd. If shadow passwords (described in "Creating a Shadow Password File") are enabled, the /etc/shadow file is checked.

Similarly, the grpck(1M) command verifies all entries in the /etc/group file. The default group file to be checked is /etc/group. With either command, an alternate file may be specified on the command line.