Support for shadow passwords has been enhanced significantly for Red Hat Linux
6.1. Shadow passwords are a method of improving system security by
moving the encrypted passwords (normally found in
/etc/passwd) to another file with more restrictive
file access permissions. During the installation, 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 a few 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.
