Start by deciding what must keep working when a component fails. Plan how to preserve data and send requests to healthy nodes.
- List each component: application nodes, database, uploaded files, background jobs, and external services. Note which components write data.
- Choose how state will stay consistent across nodes. Plan database replication and failover separately from application files, sessions, and scheduled jobs.
- Decide how requests reach healthy nodes. Choose a health check that can detect when the application is unusable.
- Place redundant components so one host failure does not remove all copies. Give the remaining nodes enough capacity to handle the workload.
- Test a controlled failure, recovery, and return to normal operation. Check data consistency as well as availability.
Cloud VPS HA groups control VM placement. Configure replication and traffic failover separately. For App Hosting, ask support to review the topology and the application's supported clustering method before migrating. Backups remain necessary for recovery from deletion or corrupted data.