Practice Exercise: Managing Passwords and User Authentication in Linux
Objectives
- Learn the importance of strong password policies in Linux.
- Understand how to manage user passwords securely.
- Explore techniques for enhancing user authentication and system security.
- Practice working with password-related commands in Linux.
Scenario
Effective password management and user authentication are crucial components of Linux system security. In this exercise, you will dive into the world of Linux passwords. You will learn how to set strong password policies, manage user passwords securely, and employ techniques to enhance user authentication and overall system security.
Tasks
Task 1: Managing User Passwords
- Explore methods for managing user passwords in Linux.
- Explain how passwords are stored and encrypted in the
/etc/shadowfile. - Demonstrate how to change a user's password using the
passwdcommand. - Emphasize the importance of password privacy and confidentiality.
[intern@intern-a1t-inf-lnx1 ~]$ passwd Changing password for intern. Current password: New password: Retype new password: passwd: password updated successfully
Task 2: Password Aging and Expiry
- Discuss the concept of password aging and expiry.
- Explain how password aging policies can enhance security.
- Demonstrate how to set password aging parameters using the
chagecommand. - Provide examples of configuring password expiration for user accounts.
[intern@intern-a1t-inf-lnx1 ~]$ chage -l intern Last password change : Sep 20, 2023 Password expires : never Password inactive : never Account expires : never Minimum number of days between password change : 0 Maximum number of days between password change : 99999 Number of days of warning before password expires : 7 [intern@intern-a1t-inf-lnx1 ~]$ sudo chage -E 2024-01-01 intern [intern@intern-a1t-inf-lnx1 ~]$ sudo chage -l intern Last password change : Sep 20, 2023 Password expires : never Password inactive : never Account expires : Jan 01, 2024 Minimum number of days between password change : 0 Maximum number of days between password change : 99999 Number of days of warning before password expires : 7 [intern@intern-a1t-inf-lnx1 ~]$ sudo chage -m 100 intern [intern@intern-a1t-inf-lnx1 ~]$ sudo chage -l intern Last password change : Sep 20, 2023 Password expires : never Password inactive : never Account expires : Jan 01, 2024 Minimum number of days between password change : 100 Maximum number of days between password change : 99999 Number of days of warning before password expires : 7 [intern@intern-a1t-inf-lnx1 ~]$ sudo chage -M 365 intern [intern@intern-a1t-inf-lnx1 ~]$ sudo chage -l intern Last password change : Sep 20, 2023 Password expires : Sep 19, 2024 Password inactive : never Account expires : Jan 01, 2024 Minimum number of days between password change : 100 Maximum number of days between password change : 365 Number of days of warning before password expires : 7 [intern@intern-a1t-inf-lnx1 ~]$ sudo chage -d 0 new_user [intern@intern-a1t-inf-lnx1 ~]$ sudo chage -l new_user Last password change : password must be changed Password expires : password must be changed Password inactive : password must be changed Account expires : never Minimum number of days between password change : 0 Maximum number of days between password change : 99999 Number of days of warning before password expires : 7
Conclusion:
Effective password management and user authentication are essential for maintaining Linux system security. In this exercise, you've learned about strong password policies, secure password management, password aging, and two-factor authentication. By implementing these practices and following security best practices, you can significantly enhance the security of your Linux systems and protect against unauthorized access.