How much does enabling DR in Azure cost you

How much does enabling disaster recovery in Azure really cost your customer when enabling Microsoft’s BCDR features on their VMs? It’s a question that often looms over cloud architects and other Microsoft Partners. As organizations increasingly rely on Azure Virtual Machines for critical workloads, understanding the financial implications of implementing a robust DR strategy becomes paramount.

Today, we will delve into the specifics: from ASR licensing costs per VM to network egress charges for replicating data across Azure regions so that you can gain clarity on the true cost of safeguarding your customer’s VMs and discover practical insights to optimize their DR setup.

Azure provides an integrated disaster recovery solution for Azure Virtual Machines via Azure Site Recovery (ASR). Beyond its extensive global coverage, Azure boasts the industry’s most comprehensive resiliency approach. This includes mitigating rack-level failures using Availability Sets, safeguarding against data centre outages with Availability Zones, and ensuring protection during large-scale incidents through failover to separate regions using ASR. Frequently, users inquire about the costs related to configuring DR for Azure VMs, and we’ve actively addressed this concern.

Costs while using ASR Configuring disaster recovery for Azure VMs using ASR will incur the following charges:

- ASR licensing cost per VM.

- Network egress costs cover the expenses associated with replicating data changes from the source VM disks to another Azure region. When using Azure Site Recovery (ASR), it employs built-in compression to reduce the data transfer requirements by approximately 60 percent.

- Storage costs on the recovery site are usually aligned with the storage costs in the source region. Additionally, any extra storage required to maintain recovery points as snapshots for future restoration is factored into the overall cost. You can look at this Example BCDR Cost Calculation for estimating DR costs for a three-tier application using 6 virtual machines. All the services are pre-configured in the cost calculator. The 6 virtual machines have 12 Standard HDD disks and 6 Premium SSD disks. Therefore, there will be 18 disks created in the DR region. Each standard disk is expected to have data change at a rate of 10 GB per day and each premium disk is expected to have data change at a rate of 20 GB per day. The daily data change rate will be the storage snapshot charges considering the recovery point retention to be 24 hours, which is the default value.

ASR uses compression to reduce the data to be transferred from source region to target region and the compression ratio usually is around 50 percent. So, 40 percent of the total data changes will be transferred between regions, which comes out to be about 3 TB per month across all the 6 VMs. The sample cost calculator has all these charges listed.

To understand how pricing might vary for your customer’s specific scenario, adjust the relevant parameters to estimate costs. You can input the number of virtual machines (VMs) to calculate the Azure Site Recovery (ASR) license cost. Additionally, consider the number and type of managed disks, as well as the expected total data change rate across all VMs, to estimate storage costs in the disaster recovery (DR) region. Furthermore, after applying a compression factor of 0.4, you can determine the bandwidth costs incurred for data transfer between regions within a month.

In addition to the above costs, you will incur additional Compute costs for the VMs created as part of a disaster recovery drill using Test failover operation or the actual disaster recovery using failover operation. You also pay for any resources such as load balancers and public IPs created beforehand which are required for the application along with the VMs to work properly when failed over.

Disaster Recovery between Azure regions is available in all Azure regions where ASR is available: - Region Support for ASR

Further resources: - Get started by configuring disaster recovery for Azure VMs. - Learn more about the supported configurations for replicating Azure VMs.

If you still feel lost and need more understanding in offering such solutions to your customers, do contact your Surestep Ambassador at This email address is being protected from spambots. You need JavaScript enabled to view it. so that we can assist with your customer’s BCDR requirements using Azure.