VM Preparation Script

This script (vm-prep.sh) is designed to prepare a virtual machine (VM) for reuse or distribution by performing a series of cleanup and reset tasks. It ensures that sensitive data, user accounts, and system-specific configurations are removed or reset.

Features

The script performs the following actions:

1. Confirmation Prompt:

   • Displays a warning message to the user.
   • Requires the user to type vmprep to proceed, ensuring intentional execution.

2. Root Privilege Check:

   • Ensures the script is run with root privileges. If not, it exits with an error.

3. User Account Cleanup:

   • Deletes all user accounts with a UID greater than or equal to 1000, except for the nobody user.
   • Allows additional user accounts to be deleted by passing their usernames as arguments to the script.

4. Hostname Reset:

   • Clears the contents of /etc/hostname.
   • Resets the hostname to localhost using hostnamectl.

5. Netplan Configuration Cleanup:

   • Removes the /etc/netplan/50-cloud-init.yaml file if it exists.

6. Machine ID Reset:

   • Clears the contents of /etc/machine-id.
   • Removes and recreates the symbolic link for /var/lib/dbus/machine-id.

7. Cloud-Init Cleanup:

   • Runs cloud-init clean to reset cloud-init state.

8. Root Password Disable:

   • Disables the root account password by running passwd -dl root.

9. Shell History Cleanup:

   • Clears the shell history for the current user.

10. Log and Temporary File Cleanup:

    • Deletes all files in /var/log, /tmp, and /var/tmp.

11. Shutdown:

    • Shuts down the system immediately after completing all tasks.

Usage

1. Run script logged in to console directly root

      bash <(curl -s https://raw.githubusercontent.com/atbakken/vm-prep/main/vm-prep.sh)

2. Confirm execution.

Warnings

• Irreversible Changes: This script makes irreversible changes to the system. Use it with caution.
• Root Privileges Required: The script must be run as root.
• Shutdown: The system will shut down automatically after the script completes.

Customization

• To exclude specific users from deletion, modify the awk command in the users_to_delete section.
• To add additional cleanup tasks, append them to the script before the shutdown command.

Logs

• The script does not currently log its actions. If logging is required, you can redirect output to a log file by modifying the script.

Disclaimer

Use this script at your own risk. Ensure you understand its functionality before running it on a production system.