A region-failover runbook with per-step timing and the exact rollback trigger - drill-ready

Act as a Site Reliability Engineering Director responsible for business continuity at a critical infrastructure company. Create a disaster recovery plan. **System Architecture**: {{system_architecture}} (brief description of current architecture, cloud providers, critical components) **Criticality Tiers**: {{criticality_tiers}} (Tier 1: revenue-impacting, Tier 2: customer-facing non-revenue, Tier 3: internal tools) **RPO/RTO Targets**: {{rpo_rto_targets}} (Recovery Point Objective and Recovery Time Objective per tier) **Compliance Requirements**: {{compliance_requirements}} (industry regulations requiring DR, audit requirements) Create the complete DR plan: 1. **DR Strategy Selection** - Backup & Restore, Pilot Light, Warm Standby, Hot Standby, Active-Active for each tier 2. **RPO/RTO Matrix** - Per service/component: current RPO/RTO, target RPO/RTO, gap analysis, mitigation plan 3. **Backup Strategy** - Database backups (full, incremental, continuous), file/object storage replication, configuration backup, code/artifact backup 4. **Infrastructure as Code Recovery** - Terraform/CloudFormation state backup, full environment recreation time, state versioning 5. **Database Recovery** - Point-in-time recovery procedures, cross-region read replica promotion, manual failover steps with timing 6. **Failover Procedures** - DNS failover (Route53 health checks), load balancer reconfiguration, auto-scaling group adjustments 7. **Runbook Library** - Step-by-step runbooks for: database failover, complete region failover, single service recovery, data corruption recovery 8. **Communication Plan** - Incident commander rotation, customer communication templates, status page updates, stakeholder notification tree 9. **Chaos Engineering** - Monthly chaos experiments (region shutdown, AZ failure, network partition), Game Day schedule, failure injection tools (Gremlin/Litmus) 10. **Testing Schedule** - Quarterly DR drills, tabletop exercises, full failover tests, automated DR testing in staging 11. **Dependencies Mapping** - External dependency failure impact (payment gateway, auth provider, CDN), vendor DR commitments 12. **Cost Analysis** - DR infrastructure costs per strategy, cost of downtime per hour, ROI of DR investment 13. **Post-Incident Recovery** - Root cause analysis template, lessons learned process, plan updates, readiness score tracking Include the actual runbook for complete region failover with timing estimates for each step.