Disaster Recovery

RTO & RPO

RTO & RPO

DR Strategies

• Backup & Restore

  • High RPO & RTO but cheapest

Backup & Restore DR

• Pilot Light

  • Critical part of the application is in the cloud (DB)

Pilot Light DR

• Warm Standby

  • Full system is up and running with a minimum scale

  • Upon disaster, scale up for production load

Warm standby DR

• Hot Site / Multi Site

  • Lowest RTO but expensive

  • Full Production Sacle is running on AWS and on premise

On premise & on AWS DR

Multi Site DR

Disaster Recovery Tips

• Backup

  • EBS snapshot, RDS automated backups / snapshots, etc.

  • Regular pushes to S3 / S3 IA / Glacier with lifecycle policy, Cross Region Replication

  • From on-premise: Snowball / Storage Gateway

• High Availability

  • Use Route53 to migrate DNS over from Region to Region

  • RDS Multi-AZ, ElastiCache Multi-AZ, EFS, S3

  • Site to site VPN as a recovery from Direct Connect

• Replication

  • RDS Replication (cross region), AWS Aurora + Global Database

  • Database replication from on-premise to RDS

  • Storage Gateway

• Automation

  • CloudFormation / Elastic Beanstalk to recreate a whole new environment

  • Recover / reboot EC2 instances with CloudWatch if alarms fail

  • AWS Lambda for customized automations

• Chaos

  • Netlflix has a "simian-army" randomly terminating EC2