AWS Elastic Disaster Recovery Cheat Sheet

It is a fully managed service providing fast, reliable, and cost-efficient disaster recovery for physical, virtual, and cloud-based Amazon Web Services (AWS) servers.

It continuously replicates block-level data from the source environment, such as on-premises infrastructure or another cloud provider, to a staging area subnet in AWS. In the event of a disaster or during a drill, AWS DRS enables the rapid launch of fully operational recovery instances in AWS, ensuring minimal downtime and data loss.

Features

• Continuous Replication

  • Block-level replication from on-premises or cloud to AWS.

• Automated Orchestration

  • Automates failover, recovery, and failback operations.

• Non-disruptive Testing

  • Run drills without affecting production environments.

• Point-in-Time Recovery

  • Supports crash-consistent and point-in-time snapshots.

• Broad OS Support

  • Works with Windows, Linux, and various distributions.

• Cross-Region and Cross-AZ Failover

  • Enables regional and zonal disaster recovery within AWS.

• Integration with AWS Services

  • Integrates with CloudWatch, CloudTrail, IAM, and AWS Systems Manager.



• Agent-based Replication

  • A Lightweight agent is installed on source machines.

Supported Sources: On-premises (VMware, Hyper-V, physical servers), AWS EC2 instances, other cloud providers (via custom setup).

Use Cases:

• Set up DR for physical or virtual data centers in AWS.
• Protect workloads hosted in other clouds (e.g., Azure, GCP) by replicating to AWS.
• Protect workloads within AWS by replicating EC2 instances to a different region.
• Lift and shift applications into AWS with near-zero downtime.
• Meet RTO/RPO targets for regulatory or business continuity requirements.
• Conduct failover tests without interrupting live workloads.

Security:

• Encryption in Transit and at Rest: Data is encrypted using TLS during transit and optionally with EBS encryption at rest.

• IAM Role-based Access Control: Restrict DRS access using IAM policies and roles.

• VPC Isolation: Replicated instances can be launched into isolated VPCs.

• CloudTrail Logging: All DRS activities are recorded for audit.

• Support for PrivateLink: Use AWS PrivateLink to avoid exposing data to the public internet.

Pricing:

• Replication Charge: $0.028 per hour per source server (approx. $20/month).

• Staging Resources:

  • EBS Snapshots: Charged per GB/month.

  • Staging Area EC2: Based on instance type and storage.

• Drill/Recovery Costs:

  • EC2, EBS, and other services used during failover or drills are billed separately.

• No Charge for Failback: Data sent from AWS back to the source is not charged by DRS, but outbound data transfer fees apply.

💡 Tip: You can reduce costs by cleaning up recovery instances and EBS volumes post-drill.

References:

What is Elastic Disaster Recovery? – AWS Elastic Disaster Recovery

Disaster Recovery Pricing | AWS Elastic Disaster Recovery | Amazon Web Services

Getting started with AWS Elastic Disaster Recovery – AWS Elastic Disaster Recovery