failover-testing

name	failover-testing
description	Test failover without disruption — isolated VNet, checklist, cadence

Failover Testing

When to use this skill

• Quarterly DR drill
• Post-change validation

Key concepts

• Test failover runs in an isolated target VNet — does not affect production replication.
• Validation checklist: VM boot, app health, DB connectivity, ingress test, dependency reachability, scripts ran.
• Cadence: monthly for tier-1, quarterly for tier-2, semi-annual for tier-3.
• Always clean up test failover resources to avoid orphan cost.
• Measure actual RTO/RPO each test and compare to commitment.

Common pitfalls

• Skipping cleanup — orphaned test VMs/disks accrue charges.
• Test passing because the isolated network masked the real DNS cutover issue.
• Doing test failovers only at the infra layer without app-level smoke tests.

References

• Microsoft Learn: search for "Failover Testing Azure VM" on https://learn.microsoft.com

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Validation-first: verify every Azure fact against the Microsoft Learn MCP server (cite the Learn URL); Learn overrides built-in knowledge. If no Learn MCP server is configured, flag the answer ⚠️ unverified and mark specs as indicative. Analysis only — verify against Microsoft documentation before applying.