AZ-305 Design infrastructure solutions Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  Azure Site Recovery

  Why it's wrong here

  Azure Site Recovery is a disaster recovery service that continuously replicates an Azure VM's disks to a secondary Azure region, but it is not a backup solution. Its RPO can be as low as 30 seconds, and it uses recovery points for planned/unplanned failover, not for long-term point-in-time restore of previous states. It does not offer backup retention policies, granular item-level recovery, or the same multi-day application-consistent backup cadence that Azure Backup provides. Therefore, for a dedicated backup strategy, Site Recovery can complement but not replace Azure Backup.

• ✗

  Azure Files

  Why it's wrong here

  Azure Files provides fully managed SMB and NFS file shares in the cloud, intended for shared access or lift-and-shift file workloads, not for backing up Azure VMs. It can serve as a target for an in-guest file copy or for manual DB backups, but it does not orchestrate VM snapshots, capture the VM's virtual hard disks, or restore an entire VM after an outage. A proper Azure VM backup requires the orchestration and snapshot integration of Azure Backup, not simply copying files to a share. Thus, Azure Files is not a valid VM backup service.

• ✗

  Azure Disk Backup

  Why it's wrong here

  Azure Disk Backup creates scheduled incremental snapshots of a single Azure managed disk, but these snapshots are disk-level, not VM-level. It doesn't invoke VSS inside the guest OS, so open files and databases may not be flushed to a consistent state, which can cause data corruption or an unusable boot volume after restore. It also cannot consolidate the multiple disks of a VM into a single point-in-time application-consistent recovery point. Because of that, Azure Disk Backup alone is not an application-consistent VM backup and should only be used for disk-specific scenarios.

• ✓

  Azure Backup

  Why this is correct

  Azure Backup is the native backup service for Azure VMs; it installs an extension that initiates VSS on Windows (and file-consistent snapshots on Linux) to produce application-consistent recovery points. The snapshots are stored in a Recovery Services vault, which can be configured for locally redundant or geo-redundant storage, enabling cross-region restores in the paired region. Azure Backup also provides customizable retention policies, multiple scheduled backups per day, and the ability to restore the full VM, individual files, or disks. This combination of VSS-based consistency, vault storage, and policy-based retention makes it the correct choice for this VM backup strategy.

Go deeper

Related to this question