Plan DR Before You Implement

Before you begin to protect any workloads using Azure Site Recovery, allocate sufficient bandwidth, based on your daily data-change rate, to meet your desired recovery point objective (RPO). Be sure to deploy the right number of configuration servers and process servers on-premises. Azure Site Recovery Capacity Planner will analyze your on-premise hypervisor and your internet connectivity to Azure and will advise on the infrastructure you need to protect your workloads using ASR.


The tool provides the following details:


Compatibility assessment

  • VM eligibility assessment, based on number of disks, disk size, IOPS, churn, boot type (EFI/BIOS), and OS version

Network bandwidth need versus RPO assessment

  • Estimated network bandwidth that's required for delta replication

  • Throughput that Site Recovery can get from on-premises to Azure

  • Number of VMs to batch, based on the estimated bandwidth to complete initial replication in a given amount of time

  • RPO that can be achieved for a given bandwidth

  • Impact on the desired RPO if lower bandwidth is provisioned

Azure infrastructure requirements

  • Storage type (standard or premium storage) requirement for each VM

  • Total number of standard and premium storage accounts to be set up for replication (Includes cache storage accounts)

  • Storage-account naming suggestions, based on Storage guidance

  • Number of Azure cores to be set up before test failover or failover on the subscription

  • Azure VM-recommended size for each on-premises VM

On-premises infrastructure requirements

  • Required number of configuration servers and process servers to be deployed on-premises

Estimated disaster recovery cost to Azure


  • Estimated total disaster recovery cost to Azure: compute, storage, network, and Site Recovery license cost

  • Detail cost analysis per VM

A report output is shown below:

The ASR Capacity Planner is an essential tool that will give you an understanding of costs, infrastructure and the RPOs you can expect to achieve when using ASR.


For more information please get in contact with the team or visit this Microsoft link.


We hope this blog post will help your ASR journey!


Many Thanks, the A4S Team!


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