Guide & Glossary

Safe script workflow

1. Read the script from top to bottom before running it.
2. Check if it uses sudo, and confirm every privileged command makes sense to you.
3. Run on a test machine first when possible.
4. Keep backups for files you might change (network configs, service configs, user data).
5. Run one script at a time and verify output before moving on.

Glossary

• Bash: A command-line shell used to run commands and scripts.
• Script: A text file containing commands executed in sequence.
• sudo: Run a command with elevated privileges (administrator/root).
• chmod: Change file permissions (read/write/execute).
• chown: Change file owner and group.
• systemctl: Manage Linux services with systemd.
• journalctl: View systemd logs.
• nmcli: Command-line tool for NetworkManager.
• tar: Archive files/folders for backup and restore.
• firewalld: Firewall service managed with firewall-cmd.

Troubleshooting quick fixes

• permission denied
  You may be missing execute permission. Run chmod +x script.sh then try again.
• command not found
  Install the required package (example: nmcli is usually from NetworkManager tools).
• service not found
  Confirm service name with systemctl list-unit-files --type=service.
• network disconnected after change
  Use the DHCP revert script in the library or reconnect from a local console.
• archive restore failed
  Verify file path, destination permissions, and test archive integrity with tar -tzf backup.tar.gz.