Chapter 6

Administrator's work

We learn concept of user, group and password for system management. We have to understand some commands which create/change/delete users and groups. We also learn command which changes password.
This chapter explains about groupad, groupdel, gropmod, useradd, userdel, usermod, passwd, vipw, vigr, su and sudo command. It also explains about passwd , group, shadow and gshadow files under /etc directory.

Contents of this Chapter

6.1 Group and User
6.1.1 User
6.1.2 Create User
6.1.3 Modify User Account
6.1.4 Deleting User Account
6.1.5 Group
6.1.6 Creating Group
6.1.7 Modifying registered Group's information
6.1.8 Deleting Group
6.2 Password and Password File
6.2.1 Password File (/etc/passwd)
6.2.2 Group File (/etc/group)
6.2.3 Password
6.2.4 Shadow File (/etc/shadow)
6.2.5 Group Shadow File (/etc/gshadow)
6.2.6 Modify Shadow File
6.3 Initial provided User accounts and Groups
6.3.1 General User Account and Group
6.3.2 root User
6.3.3 su Command
6.3.4 sudo Command which executes by root authority
6.4 Exercise
6.5 The chapter test