Profile Applicability:

  • Level 2

Description:

Replication settings in AWS Elastic Disaster Recovery (EDR) determine how source servers replicate data to AWS. This includes staging area configuration, replication server instance type, subnet selection, and encryption options. Proper configuration ensures reliable, secure, and optimized data replication for disaster recovery readiness.

Rationale:

Proper replication settings ensure:

  • Efficient, consistent replication with minimal data loss

  • Alignment with security and networking policies

  • Cost-effective use of AWS resources

  • Compatibility with application recovery objectives

Default Value:

Default replication settings are auto-generated when a source server is added, but may not align with organizational policies or performance requirements.

Impact:

Pros:
 • Enables reliable replication and faster recovery times
• Allows control over cost, performance, and security
 • Prevents replication errors or failures during failover

Cons:
 • Requires initial customization per server or group
• Misconfiguration may result in excessive costs or failed recoveries
 • Needs to be reviewed if the environment or architecture changes

Pre-requisites:

IAM Permissions Required:
 drs:GetReplicationConfiguration
 drs:UpdateReplicationConfiguration
 ec2:DescribeSubnets, ec2:DescribeSecurityGroups
 Access to network, instance type, and encryption configuration

Remediation:

Test Plan:

Using AWS Console:

  1. Log in to the AWS Management Console
  2.  Navigate to Elastic Disaster Recovery (EDR)
  3. Go to Source Servers and select a server
  4. Click on Replication settings
  5. Confirm values such as:

  • Staging area subnet

  • Instance type

  • Security group

  • Data routing options

  • Disk encryption
    • Verify that settings are compliant with performance, cost, and security expectations

Using AWS CLI:

aws drs get-replication-configuration \
  --source-server-id s-xxxxxxxxxxxxxxxxx

Implementation Plan:

Using AWS Console:

  1. Go to Elastic Disaster Recovery Console
  2.  Select a source server
  3. Click Replication settings > Edit settings
  4.  Update values:

  • Choose the correct staging area subnet

  • Select instance type based on workload requirements

  • Apply appropriate security group

  • Enable encryption if required

  • Add tags for management or cost tracking
     • Click     Save changes

Using AWS CLI:

aws drs update-replication-configuration \
  --source-server-id s-xxxxxxxxxxxxxxxxx \
  --staging-area-subnet-id subnet-xxxxxxxx \
  --replication-server-instance-type t3.medium \
  --security-group-ids sg-xxxxxxxxxxxxxxxxx \
  --use-dedicated-replication-server false \
  --ebs-encryption enabled

Backout Plan:

Using AWS Console:

  1. Open the same Replication settings page
  2. Revert to previous values manually
  3. Review saved settings from documentation or recovery plan

Using AWS CLI:

aws drs update-replication-configuration \
  --source-server-id s-xxxxxxxxxxxxxxxxx \
  --replication-server-instance-type t3.small \
  --staging-area-subnet-id subnet-yyyyyyyy

References: