Backups

Commvault backs up all of the virtual machines identified on the Content tab for a subclient.

What Gets Backed Up

The following items are included in backups:

• Azure Generation 1 and Azure Generation 2 virtual machines

• Disks configured by users through the Azure portal, including disks configured on Standard and Premium storage accounts

• Virtual machines (VMs) with encrypted blobs. These VMs can be protected and fully recovered. However, guest file recovery of these VMs is not currently supported.

• For Azure Resource Manager deployments, virtual machines that are configured with Azure unmanaged and managed disks. From these backups, you can restore full virtual machines and restore guest files and folders.

• Unmanaged and managed disks with Changed Block Tracking (CBT) enabled

  For more information, see Changed Block Tracking for IntelliSnap Backups - Microsoft Azure.

  Virtual machines that are encrypted by Azure Key Vault. Backups of these VMs can include the operating system information, the data disks information, secrets (for example, token and password information), and encryption keys (for example, algorithm information). The encryption keys can be managed by Microsoft or by customers.

• For Azure-managed disks, information about the configured Availability Zones, which are specific (physical) locations within an Azure region.

• Azure-managed disks that are enabled with encryption at the host, on Windows or Linux VMs.

What Does Not Get Backed Up

The following items are not included in backups:

• Temporary disks that are automatically configured by Azure when a virtual machine is created

• Files or network drives that are shared in Azure and mounted on a virtual machine

• Azure Ultra SSD-managed disks

  Due to a Microsoft limitation, snapshots of Ultra SSD-managed disks are not supported. When Ultra SSD-managed disks reside on a virtual machine with other supported disks, during backups, the Ultra SSD-managed disks are skipped. The other disks on the virtual machine are backed up.

  You can back up your Ultra SSD-managed disks using the Windows File System Agent. For more information, see Backups Using the Windows File System Agent.

IntelliSnap Backup Process

The IntelliSnap backup operation includes the following:

1. Discover the virtual machine in the Azure Cloud based on subclient settings.

2. Create a client computer entry for each virtual machine discovered.

3. Identify the virtual machines targeted for backup and the VSA proxies that can be used to perform backups. VSA proxies can be installed on Azure virtual machines or on local physical or virtual machines. For Azure Classic backups, the VSA proxy must have a Microsoft Azure Management Certificate installed.

4. Identify the disks associated with virtual machines targeted for backup.

5. Create snapshot on the Virtual machine in the Azure Cloud.
   Note that Azure snapshots are crash-consistent backups.

6. If Changed Block Tracking (CBT) is enabled for the subclient, the system will generate the Change IDs for all disks and store them in the index.

7. Complete the backup job uploading all required files to index.

8. If the virtual machine is encrypted using Azure Key Vault, the key information and secret information will be included in the backup as well. This is required at the time of restore in order to boot up the VM successfully by restoring the backed up encrypted files (secrets and keys).

Backup Copy Process

The backup copy operation includes the following:

1. Identify the IntelliSnap job for which the backup copy job is running.

2. Identify all the virtual machines selected for the IntelliSnap backup during discovery process.

3. Identify the virtual machines/disks snapshots created during IntelliSnap backup job.

4. Assign backup streams to the proxies in a round-robin sequence, or assign all the virtual machines if single proxy is selected for backup copy operations under subclient properties.

5. Engage the Virtual Server File System driver (VSCloudFS). The VSCloudFS driver is an on-demand driver that is used to upload pages and read data to or from the Azure cloud. The driver is used for backups and restores of Azure virtual machines and for conversion of virtual machines to Azure.

6. If backup type is Cyclic Redundancy Check (CRC): Read extents from snapshots, compute CRC and write to backup media and complete the backup job

7. If backup type is CBT: With this option enabled at the subclient level, only the extents that have changed in between consecutive CBT-enabled jobs are backed up.

8. Clean up the Azure mount point, and complete the backup job.

9. If the virtual machine is encrypted using Azure Key Vault, the key information and secret information will be included in the backup as well. This is required at the time of restore in order to boot up the VM successfully by restoring the backed up encrypted files (secrets and keys).