HP Certified: HP-UX System Administration

Every user on a system has a login name and password and is a member of one or more groups. A new user is created using the useradd command, and the password for the newly created user is assigned with the help of the passwd command. The useradd command uses default options for new users that can be listed and modified using the useradd -D command. For deleting a user, you use the userdel command. User properties or attributes can be modified with the help of the usermod command. Inactivity and expiration limits can also be imposed on users after which a user account is disabled.

Like users, groups can be added, deleted, and modified using the groupadd , groupdel , and groupmod commands, respectively. A user can be a member of more than one group , and the id and groups commands can be used to list a user's group membership.

Both the /etc/passwd and /etc/group files follow a defined file syntax where every field of a line is separated by a colon character. Consistency of these files can be checked using the pwck and grpck commands. The vipw editor is used to manually edit the /etc/passwd file. When a new user is created, default configuration files are copied into the user's home directory. These files are stored in the /etc/skel directory. SAM can also be used to create and manage users and groups and define user templates.