"adduser/usermod/userdel" - Commands to Manage Users

This section provides a tutorial example on how to adding a new user, modifying a user setting to join a group, deleting user's login access and removing his home directory.

There 3 primary commands to manage users on Linux systems:

1. "adduser" for adding a new user, "joe", and setting his password.

herong$ sudo adduser joe

herong$ sudo passwd joe
  (set joe's password)

2. "usermod" for modifying user's settings, like adding "joe" to the "dba" group, or changing joe's home directory.

herong$ sudo usermod -aG dba joe

herong$ sudo usermod --home /new_home/herong joe

3. "userdel" for removing a user,

herong$ sudo userdel joe
  (deleting joe's login access)

herong$ sudo userdel -r joe
  (deleting joe's login access and removing his home directory)

Table of Contents

 About This Book

 Introduction to Linux Systems

 Cockpit - Web Portal for Administrator

 Process Management

 Files and Directories

Users and Groups

 Manage User Groups

 Group Access Permissions on Files

 "sudo" Command and Privilege

"adduser/usermod/userdel" - Commands to Manage Users

 System Users and Groups

 Add Users and Groups Manually

 File Systems

 Block Devices and Partitions

 LVM (Logical Volume Manager)

 Installing CentOS

 SELinux - Security-Enhanced Linux

 Network Connection on CentOS

 Software Package Manager on CentOS - DNF and YUM

 vsftpd - Very Secure FTP Daemon

 Postfix - Mail Transport Agent (MTA)

 Dovecot - IMAP and POP3 Server

 Email Client Tools - Mail User Agents (MUA)

 LDAP (Lightweight Directory Access Protocol)

 Administrative Tasks

 References

 Full Version in PDF/EPUB