Business continuity and disaster recovery (BCDR) planning is essential for any organization to bounce back from disruption. While Azure Active Directory (AD) itself isn’t directly used for disaster recovery, it plays a supporting role, particularly when recovering your on-premises AD. BCDR implementation can be done with Microsoft Azure’s native disaster recovery as a service (DRaaS) known as Azure Site Recovery (ASR).
Why do you need a BCDR strategy?
Disasters, both anticipated and unforeseen, can and will happen. Human error, cyberattacks, hardware failure, or natural calamities can potentially harm your business, reputation, and workflow. A BCDR plan acts as insurance for your organization; without one, the likelihood of your business surviving a major disaster is quite low.
Azure Site Recovery
Azure Site Recovery (ASR) is a managed service within the Azure cloud platform for disaster recovery. It functions by replicating your on-premises machines and Azure Virtual Machines (VMs) to a geographically separate location. This distinct copy acts as a safeguard, ensuring your applications remain operational even when disrupted.
Key functionalities of Azure Site Recovery
- Replication: ASR continuously copies your applications and data to a separate location, typically another Azure region. This serves as a backup in case something goes wrong at your primary location.
- Failover: Failover is the process of automatically switching operations from a primary site to a secondary site. Upon detecting a disaster at the primary site, ASR initiates a pre-defined failover process. It uses the replicated data to automatically provision VMs that host your applications and establishes network mappings for communication. With VMs up and running in the secondary site, your applications become accessible again, minimizing downtime.
- Failback: Failback is the process of transitioning your applications and data back to the original (primary) location after a disaster has been resolved. ASR ensures any changes made to your applications while operating in the secondary site are synchronized with the primary site, minimizing data loss.
- Testing: ASR allows for non-disruptive failover drills to test your DR plan and identify potential issues before a real-world scenario unfolds.
Configuring Azure Site Recovery
- Ensure Active Azure subscription: Determine the location of your critical VMs or machines you want to protect.
- Choose a separate Azure region: Select a geographically separate Azure region for replicating your data.
- Create a recovery services vault: This central vault in Azure serves as the hub for managing ASR configurations and disaster recovery plans.
- Prepare the source environment:
- On-premises machines: Install the Azure Site Recovery Provider on your on-premises machines to enable communication with ASR.
- Azure VMs: No additional configuration is needed for existing Azure VMs.
- Azure stack VMs: Refer to Microsoft’s documentation for specific instructions on preparing Azure Stack VMs for ASR.
- Enable replication:
- Navigate to the Recovery Services Vault in the Azure portal.
- Select “Replication Items” and then “Azure VMs” or “On-premises machines” depending on your source.
- Specify the VMs or machines you want to replicate.
- Configure replication settings like schedule and recovery points.
- Configure network connectivity: Define how replicated data will transfer between your source and target environment.
- Create a recovery plan:
- Establish a structured approach for orchestrating failover and failback procedures.
- Define the order in which VMs are brought online during failover and reversed during failback.
- Specify any manual actions required during the recovery process.
Benefits of utilizing Azure Site Recovery
- Reduced Downtime: By enabling rapid failover to a secondary site, ASR minimizes downtime during outages.
- Cost-Effectiveness: ASR leverages a pay-as-you-go billing model, so you only pay for resources used during replication and failover.
- Improved Business Continuity: ASR ensures application availability even during disasters, safeguarding your business operations and reputation.
- Simplified Management: The Azure portal streamlines DR configuration, monitoring, and failover processes.
ASR presents a viable solution for building disaster recovery (DR) for your on-premises VMware environment. It offers noteworthy advantages such as minimized downtime, cost efficiency when utilized, scalability, and streamlined management. However, it’s essential to acknowledge the dependence on a stable network connection and potential cost fluctuations. Nevertheless, for many businesses, ASR’s strengths may outweigh these considerations.