Microsoft Certified: Azure Administrator AssociateDeploy and manage Azure compute resourcesHard
A company is deploying several Azure Virtual Machines (VMs) that will host a stateful application. The application requires that if a VM fails, another VM with the exact same configuration and data should automatically become available with minimal downtime. The solution must provide high availability within a single Azure region. Which Azure feature should you use to achieve this?
- AAzure Availability Zones
- BAzure Site Recovery
- CAzure Shared Disks with Failover Cluster
- DAzure Virtual Machine Scale Sets (VMSS)
Show answer & explanationAnswer & explanation
Correct answer: C. Azure Shared Disks with Failover Cluster
For stateful applications requiring minimal downtime and automatic failover within a single region, Azure Shared Disks combined with a Windows Server Failover Cluster (WSFC) or Linux equivalent is the most appropriate solution. This allows multiple VMs to share a single disk, enabling rapid failover where the data remains accessible to the surviving node.
Why the other options are wrong
- A. Availability Zones provide resilience against datacenter failures by distributing VMs, but they don't automatically provide 'exact same configuration and data' failover for stateful applications without additional clustering.
- B. Azure Site Recovery is a disaster recovery solution for cross-region or on-premises to Azure replication, not primarily for high availability within a single region with automatic stateful failover.
- D. VMSS is for scaling out stateless applications and doesn't inherently provide shared data or automatic failover for stateful workloads without complex configurations.
Azure Shared Disks
A feature of Azure Managed Disks that allows multiple Azure VMs to concurrently attach a single disk.
- Enables building highly available clustered applications (e.g., WSFC).
- Provides shared storage for stateful workloads.
- Requires a cluster manager (e.g., Windows Server Failover Clustering) to manage disk access.
Memory trick: To share state and fail over fast, make sure your disks are shared and clustered.