What it means
Detection and switching
A failover design needs a way to detect failure, decide when switching is appropriate and route work to a usable alternative. Redundant components only help if their dependencies and operational procedures permit the switch.
Payment-state safety
Failing over an application does not resolve an uncertain remote payment result. The replacement service must access appropriate durable state and preserve operation identity. Recovery tests should consider partial outages, stale replicas, duplicated workers and the return to normal operation, not only whether a standby process starts.
Related concepts
Idempotency, Service-level agreement, Payment reconciliation.
In practice
A concrete example
A standby worker resumes payment-status checks using persisted identifiers instead of recreating payments whose original results are unknown.
Technical notes & boundaries
Failover is distinct from backup restoration. It does not inherently guarantee zero downtime, zero data loss or safe duplicate-free payment processing.
Go to the source.
Original references used for this definition. Product details and standards can change.