Skip to content

Is a Failover Strategy in Place for Critical Operations?

Type: DeepDive
Category: Availability
Audience: Infra engineers, SREs, platform leads managing availability and redundancy

🔍 What This Perspective Covers

No system is immune to failure.

This perspective verifies whether your most critical processing paths can survive machine failure, zone failure, or sudden disconnects—without human intervention.

⚠️ Failure Patterns

  • Failover is “planned” but never tested
  • Infra auto-recovers, but app logic is not restart-tolerant
  • Stateful nodes fail without handover of critical context
  • Observability gaps during failover → unclear if recovery succeeded

✅ Smarter Failover Design

✅ Critical Examples

  • Background tasks move to a healthy worker if one dies
  • API gateway can reroute across availability zones
  • DB read replicas are promoted on primary failure
  • Leader election recovers quorum-based consensus
  • External dependency is wrapped with circuit breakers and fallback paths

✅ Design Considerations

  • Classify “critical to user experience” vs. “non-critical background”
  • Simulate infrastructure chaos regularly—not just unit tests
  • Use health checks and probes to drive failover triggers
  • Ensure handoff design preserves state or tolerates partial loss
  • Log and alert failover triggers and results clearly

🧠 Principle

Failover is not a feature.
It’s a testable architectural constraint.

❓ FAQ

  • Q: Is infra-level HA (like multi-AZ) enough?
    A: No. Apps need to be designed to survive unexpected restart and failover.

  • Q: What does “simulate chaos” mean?
    A: Kill nodes. Disconnect network. Monitor outcomes.