100 Days of DevOps — Day 1: Linux User Setup with Non-Interactive Shell

This kind of setup is often used when a user account is needed for system processes, automation, or service integration but should not have direct login access. It’s an important concept in DevOps and system security.

Task Description

At xFusionCorp Industries, the system admin team required me to:

• Create a user named ammar

• Assign the user a non-interactive shell

• Perform this on App Server 3

Steps & Commands

1. Connect to App Server 3 and add password : BigGr33n

    ssh banner@stapp03.stratos.xfusioncorp.com
   

2. Create the user with a non-interactive shell

    sudo useradd -s /sbin/nologin ammar
   

   Here:

   • useradd → command to create a new user

   • -s /sbin/nologin → prevents the user from logging in interactively

3. Verify the user shell

    grep ammar /etc/passwd
   

   Output should look like this:

    ammar:x:1001:1001::/home/ammar:/sbin/nologin
   

Challenges Faced

• Remembering the difference between /sbin/nologin and /bin/false.

• Making sure I was connected to the correct server (App Server 3) before running the command.

Lessons Learned

• User management is one of the most important Linux admin skills for DevOps.

• Using a non-interactive shell ensures security for accounts that exist only for processes, not real users.

• Always double-check the server name before making changes in multi-server environments.

Conclusion

Day 1 taught me how even simple tasks like user creation play a huge role in system security and infrastructure management. This was a strong starting point for my DevOps journey.

👉 Next up: Day 2 – Temporary User Setup with Expiry