Azure Site Recovery updates | Managed Disks & Availability Sets

Azure Site Recovery team has made some significant improvements to the service during past couple of months. Recently Microsoft has announced the support for managed disks and availability sets with ASR. 

Managed Disks in ASR

Managed disks allow simplified disk management for Azure IaaS VMs and users no longer have to leverage storage accounts to store the VHD files. With ASR,  you can attach managed disks to your IaaS VMs during a failover or migration to Azure. Additional using managed disks ensure reliability for VMs placed in Availability Sets by guaranteeing that the failed over VMs are automatically placed in different storage scale units (stamps) to avoid any single point of failure.

Availability Sets in ASR

Site Recovery now supports configuring VMs into availability sets in ASR VM settings. Previously users had to leverage a script that can be integrated to the recovery plan to achieve this goal. Now you can configure availability sets before the failover so that you do not need to rely on any manual intervention.

Below are some considerations to be made when you are using these two features.

  • Managed disks are supported only in Resource manager deployment model.  
  • VMs with managed disks can only be part of availability sets with “Use managed disks” property set to Yes
  • Creation of managed disks will fail , if the replication storage account was encrypted with Storage Service Encryption (SSE). If this happens during a failover you can  either set “Use managed disks” to “No” in the Compute and Network settings for the VM and retry failover or disable protection for the vm and protect it to a storage account without Storage service encryption enabled.
  • Use this option only if you plan to migrate to Azure for any SCVMM managed/unmanaged Hyper-V VM’s Failback from Azure to on-premises Hyper-V environment is not currently supported for VMs with managed disks.
  • Disaster Recovery of Azure IaaS machines with managed disks is not supported currently.