The PPT will give you basic idea on AWS DRS service. AWS Elastic Disaster Recovery (AWS DRS) is the preferred disaster recovery service for AWS. It functions similarly to CloudEndure Disaster Recovery and is managed using the AWS Management Console. This allows for smooth integration of AWS DRS with other AWS services including AWS CloudTrail, IAM, and Amazon CloudWatch.

1. LET’S UNDERSTAND
AWS DISASTER RECOVERY
SERVICE
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2. A disaster may be classified into four types:
Human mistakes - Unintentional behaviors that result in a security
compromise, such as unintended software or database misconfiguration.
Malicious attacks - Unauthorized acts that disrupt a victim's system,
such as a denial-of-service (DoS) attack or a ransomware assault.
Natural disasters - Environmental causes such as earthquakes or floods
that trigger system breakdown.
Technical failures - A software, hardware, or facility issue, such as a
power outage or a network connectivity failure.
Disaster
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3. With quick, reliable recovery of on-premises and cloud-based
applications using inexpensive storage, light computing, and point-in-
time recovery, AWS Elastic Disaster Recovery (AWS DRS) reduces
downtime and data loss.
AWS DRS
Definition
AWS Elastic Disaster Recovery (AWS DRS) is the preferred
disaster recovery service for AWS. It functions similarly to
CloudEndure Disaster Recovery and is managed using the AWS
Management Console. This allows for smooth integration of AWS DRS
with other AWS services including AWS CloudTrail, IAM, and
Amazon CloudWatch.
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4. Elastic Disaster Recovery's Recovery Time Objective (RTO) is commonly
measured in minutes. The RTO is heavily reliant on the OS boot time.
AWS DRS RTO & RPO
The Recovery Point Objective (RPO) of Elastic Disaster Recovery is often
in the sub-second range.
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5. With AWS Elastic Disaster Recovery, you can restore your
applications on AWS from any source infrastructure on which you can
install the AWS Replication Agent and run the DRS Failback Client.
This comprises physical infrastructure, virtual machines running on
hypervisors from VMware, Microsoft, and others, as well as cloud
infrastructure from other cloud providers.
Infrastructure Supported by AWS
DRS
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6. AWS DRS Capabilities
• Supported for Windows and Linux
• Hourly metering via standard AWS billing and EULA
• Control plane Higher availability due to no cross-Region dependencies
• Supports AWS PrivateLink and AWS Direct Connect for replication and failback
• Supports AWS Region to Region replication and recovery
• Provides option to replicate not through public internet, which is a significant security benefit
• In scope for the GDPR compliance
• Supported AWS Region to Region failback with manual steps
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7. AWS DRS Process Overview
The overall procedure is as follows:
• On the source server, install the AWS Replication Agent.
• Wait till Initial Sync is complete.
• Drill instances should be launched. Run acceptance tests on the servers.
• Begin the Failover process by diverting traffic.
• Confirm that the Recovery instance was successfully deployed.
• Start a Failback to retrieve your data.
• Finish the Failback
• Return to regular operations.
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8. CloudWatch Metrics for DRS
CloudWatch metrics for DRS are as follows:
• TotalSourceServerCount is the total number of source servers.
• LagDuration - in seconds, the age of the most recent consistent
photo.
• Backlog – the quantity of data that has yet to be synchronised,
measured in bytes.
• DurationSinceLastSuccessfulRecoveryLaunch - the duration in
seconds since the previous successful Drill or Recovery instance
launch.
• ElapsedReplicationDuration - in seconds, the total length of time
this server has been replicating.
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9. The worldwide infrastructure of AWS is organized around AWS Regions
and Availability Zones. Regions provide a number of physically separated
and isolated Availability Zones that are linked by low-latency, high-
throughput, and highly redundant networking. With Availability Zones,
you can build and run applications and databases that seamlessly fail over
across zones. Availability Zones outperform typical single or multiple data
Centre architectures in terms of availability, fault tolerance, and
scalability.
Resilience in AWS Elastic Disaster
Recovery
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10. AWS DRS Point In Time States
Elastic Disaster Recovery has the following PIT state schedule:
• Every 10 minutes for the last hour
• Once an hour for the last 24 hours
• Once a day for the last 7 days (or a different retention period)
Note: In the Replication Settings, you may change the default 7-day snapshot
retention rate to anything between 1 day and 365 days.
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11. Important Links
• https://docs.aws.amazon.com/drs/latest/userguide/what-is-drs.html
• https://pages.awscloud.com/rs/112-TZM-766/images/GEN_disaster-recovery-
plan-checklist_May-2020.pdf
• https://explore.skillbuilder.aws/learn/course/external/view/elearning/11123/aw
s-elastic-disaster-recovery-a-technical-introduction
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