Last week we ran a full disaster recovery (DR) drill in a production-like environment: from incident trigger and backup restore to service verification. The exercise exposed many often-overlooked details. Here are ten condensed, practical lessons worth sharing.
- Make playbooks realistic and executable — Paper plans are often idealized. Scripts must include real failure modes (network breaks, permission issues, dependent services).
- Verify restores, not just backups — Regularly restore small samples (not just metadata) to catch corrupt or unusable backups early.
- Don’t rely on memory for dependencies — Maintain a list of external dependencies (DNS, certs, third-party APIs, auth services) with contacts and fallbacks.
- Test network and firewall rules — A successful data restore is useless if network policy prevents service access.
- Treat keys and permissions as first-class DR items — Missing private keys or temporary access often block recovery; validate credential workflows during drills.
- Recover incrementally, not all at once — Bring up core services first to validate the business flow, then restore lower-priority components.
- Make automation idempotent and reversible — Automated steps should be safe to rerun and include clean rollback paths.
- Include monitoring and alerting in the drill — After recovery, verify metrics, alert thresholds, and that people receive notifications.
- Exercise communications with non-technical teams — Simulate notifications for ops, support, legal and management; have templates ready.
- Follow each drill with a tracked improvement plan — Convert findings into an action list with owners and deadlines; close the loop before the next drill.
Conclusion: The value isn’t in “doing a drill” once — it’s in capturing failures, turning them into repeatable fixes and automation, and continuously improving resilience.
