Match The Package And Environment
- Record the product edition and package version. Read its compatibility guide.
- Check the runtime actually used by the website and any scheduled commands; CLI and web PHP may differ.
- Verify your package against its trusted distribution checksum when one is supplied.
- Use an isolated test installation and disposable data for the first deployment.
Prepare Recovery
Back up application files, database and configuration before making changes. For storage and VPN products, also account for external resources: reverting WHMCS files alone does not undo a completed NAS operation or restore a terminated VPN account. Keep backups outside the web root and protect credentials.
Validate The User Journey
- Test the administrator workflow and a separate customer session.
- Test both an expected success and an expected refusal, such as a wrong OTP or unauthorized resource.
- Confirm mail delivery, HTTPS trust and any required backend connectivity.
- Keep a record of the installed version and maintenance changes.
Use Product-Specific Instructions
The checklist is general preparation, not a replacement for the product guide. TrueNAS requirements and Email Verification requirements are intentionally separate.