Question 27

Explanation

To configure a user with a specific UID and restrict access to an interactive shell, follow these steps:

1. Create the User:

   • Run the following command to create the user sam with:

     • UID set to 1500

     • Default shell set to /sbin/nologin (restricting interactive access)

     # useradd -u 1500 -s /sbin/nologin sam

   • The option -u 1500 sets the user ID, and -s /sbin/nologin sets a non-interactive shell, preventing the user from logging in interactively.

2. Verify User Details:

   • Run the following command to display sam's user and group IDs, confirming the correct UID:

     # id sam

   • Additionally, you can check the user entry in the /etc/passwd file to confirm the shell and UID settings:

     # tail -1 /etc/passwd

3. Attempt to Access sam's Account:

   • To further confirm restricted access, try switching to the sam account:

     # su - sam

   • You should see a message indicating that access is denied or that /sbin/nologin restricts the shell.

Explanation:

• Purpose of /sbin/nologin:

  • The /sbin/nologin shell is commonly used to restrict shell access for system accounts or users who do not need interactive login capabilities. It displays a message denying access if someone tries to log in.

• Why Set a Specific UID:

  • Assigning a specific UID, like 1500, ensures user management consistency, especially in environments where UID assignments may need to follow organizational standards or unique identification for users.