Pilot Light and Warm Standby
Keep a minimal core of your workload running in a second Region (pilot light) or a scaled-down but fully functional copy (warm standby) ready to scale up.
Beyond Backup and Restore
When your RTO requirement is tighter than a few hours, Backup and Restore is insufficient. The next two DR tiers — Pilot Light and Warm Standby — keep some or all of your infrastructure running in the DR region at all times, reducing the time to recover significantly. Both strategies involve maintaining a DR environment continuously and using Route 53 health-check failover to redirect traffic during a disaster. The difference is how much of the DR environment is actively running.
Pilot Light: Core Always Running
In the Pilot Light strategy, you keep only the critical core of your system running in the DR region — typically just the database tier with continuous replication. The application servers are NOT running; instead, you maintain pre-built AMIs, launch templates, or infrastructure-as-code that can launch them quickly. Think of it as a gas pilot light that burns very small and can ignite the full flame within minutes when needed. RTO is typically 30-60 minutes.
# Pilot Light: what runs 24/7 in DR region
# - RDS Read Replica (receiving continuous replication)
# - Minimal VPC/networking (no extra cost if no data transfer)
# - Route 53 failover record (inactive, health check pointing to primary)
# What is prepared but NOT running:
# - EC2 launch template pointing to DR AMI
# - ALB (can be created in minutes)
# - ASG with desired=0, can scale to 10 on demandAll lessons in this course
- RTO, RPO, and DR Tiers
- Backup and Restore
- Pilot Light and Warm Standby
- Multi-Site Active-Active with Global Tables and Route 53