Shadow Utilities

Shadow passwords are a method of improving system security by moving the encrypted passwords (normally found in /etc/passwd) to /etc/shadow which is readable only by root. During the installation of Red Hat Linux, you were given the option of setting up shadow password protection on your system.

The shadow-utils package contains a number of utilities that support:

• Conversion from normal to shadowed passwords and back (pwconv, pwunconv)

• Verification of the password, group, and associated shadow files (pwck, grpck)

• Industry-standard methods of adding, deleting and modifying user accounts (useradd, usermod, and userdel)

• Industry-standard methods of adding, deleting, and modifying user groups (groupadd, groupmod, and groupdel)

• Industry-standard method of administering the /etc/group file (gpasswd)

Please Note

There are some additional points of interest concerning these utilities: The utilities will work properly whether shadowing is enabled or not. The utilities have been slightly modified to support Red Hat's user private group scheme. For a description of the modifications, please see the useradd man page. For more information on user private groups, please turn to the section called User Private Groups. The adduser script has been replaced with a symlink to /usr/sbin/useradd.