Skip to content

Decision criteria for option "Rebuild"

When to choose a Rebuild

  • If you already manage your infrastructure using tools like Ansible or Terraform and can redeploy your OpenStack environment in an automated way.
  • If you wish to invest time in testing, revisiting earlier design decisions, and potentially improving your application in a more deliberate, thoughtful process.

Pros

  • Current setup stays online during preparation
  • Plenty of time for testing and improvements
  • Ideal for revisiting architectural choices
  • Great way to validate Ansible/Terraform playbooks
  • Low stress and fewer surprises on migration day

Cons

  • Requires a solid understanding of your current setup and architecture
  • Temporary service names, DNS entries, and certificates may be needed for testing
  • Slightly higher initial effort for setup and validation

Overview of a Rebuild Migration

A rebuild migration allows you to set up your new infrastructure in parallel, while your existing services remain fully operational. This method gives you maximum flexibility and control.

Step-by-step process

  1. Request your destination project on Switch Cloud OpenStack

    • Contact your institution's local IT services (e.g., Informatikdienste).
    • Clearly specify that you need a new project in the Switch Cloud OpenStack environment.

  2. Request sufficient resource quotas

    • Ensure that your new project is provisioned with enough CPU, RAM, and storage to match (or exceed) what you are currently using on your existing SWITCHengines project.
    • It's helpful to estimate your peak usage to avoid delays later.

  3. Rebuild your infrastructure

    • Set up networks, subnets, security groups, key pairs, VMs, and any other components in the new project.
    • If you use Infrastructure as Code tools like Ansible or Terraform, this is a good moment to leverage them for automation and consistency.

  4. Prepare your applications

    • Reinstall your applications and ensure all services are functioning in the new environment.
    • This phase allows you to test, refine, and improve your setup without affecting the current production environment.

  5. Migrate your data

    • Copy your application and user data from the old system to the new one using tools like:
      • rsync (for files)
      • Database replication
      • Backup and restore methods
    • Ensure all necessary data is migrated incrementally and tested.

  6. Plan and execute your switch-over

    • Choose a specific cut-over date.
    • On that date:
      • Stop the old application and perform a final data sync.
      • Update your DNS records to point to the new IP addresses.
      • Start the new environment in production mode.

  7. Decommission the old project (optional) Once everything is tested and confirmed running smoothly on Switch Cloud, you may plan to decommission your old project on SWITCHengines. To decommission legacy resources on SWITCHengines, send a standard decommissioning email to: engines-support@switch.ch