Protecting AHV virtual machines with file-level backups

In most cases, Unitrends recommends that you use host-level backups to protect your AHV virtual machines. However, in some instances, you might wish to protect your VMs at the guest level in the same way you would protect physical machines, by using agent-based file-level or Windows image-level backups. Host-level and agent-based backups provide you with different options.

Use the following topics to determine whether to run host-level or agent-based backups of AHV virtual machines:

General features of AHV host-level and agent-based protection are given here:

Note:  To protect a VM with both host-level and agent-based backups, ensure that the VM's host-level and agent-based jobs do not overlap. Running both simultaneously may lead to undesirable results.

AHV protection strategy

Considerations

Host-level backups

The following apply to host-level backups:

• Quickest setup, do not need to add VMs individually or install a Unitrends agent on each VM.
• Automatically include new VMs in backup schedules. (Not supported for SLA policy schedules.)
• Leverages Nutanix REST APIs to perform application and operating system consistent backup and recovery. Application consistent protection requires that Nutanix Guest Tools (NGT) are installed and running on the virtual machine.
• Supports excluding disks from a backup. If you have a requirement to exclude data at the directory- or file-level, or if you don’t have space in your containers for snapshots of your VMs, consider using file-level backups.
• Supports recovering individual files from backups for VMs running Windows or Linux.

Agent based file-level backups

The following apply to file-level backups:

• Backup appliance treats the VM like a physical asset.
• All backup options are supported, including options to exclude files, directories, or volumes from backup, and run pre- and post-backup commands. Recommended for VMs where more granular exclusion of data is required.
• Provide application and operating system consistent backup and recovery.
• Support Windows replicas to quickly spin up a virtual replica of a failed Windows asset.

File-level application backups provide these benefits:

Note:  Application backups schedules cannot be created through SLA policies.

• SQL, Exchange, Oracle, and SharePoint backups perform application-level post backup processing, such as log truncation.
• Support all SQL database recovery models. Must run file-level application backups for all recovery models other than simple.
• Support backup of multi-node SharePoint farms.

Agent based Windows image-level backups

The following apply to Windows image-level backups:

• Assets are protected and the disk and volume level.
• Backups include the 'in use' regions of the Windows disk or volume only. Deleted regions are not included.
• Provide application consistent backup and recovery for NTFS and ReFS filesystems.
• Provide crash consistent backup and recovery for FAT, FAT32, and exFAT filesystems.
• Opt to include or exclude volumes from backup.
• Opt to run commands on the asset before or after the backup job.
• Opt to index the backup so you can search an asset's backups by filename to recover individual files. This option is set by asset (see To edit an agent-based asset for details).

Specific instances when you might want to protect VMs at the asset level are described below. For instructions on setting up file-level protection, see Protected assets.

VM type

Protection considerations

Application server hosting applications for which you need more granular control.

Use file-level application backups to select individual databases to back up and recover.

Exchange server

Use file-level application protection if more granular control is needed.

SQL server
• For simple recovery model databases, use file-level application protection for more granular control.
• For full or bulk-logged recovery model databases, use file-level application protection. (Host-level protection is not supported)

SharePoint server

Use file-level application protection. (Host-level protection is not supported.)

Oracle server

Use file-level application protection. (Host-level protection is not supported.)

Virtualized Active Directory (AD) servers for which you are not following Microsoft’s best practices

Use file-level protection.

VMs in Distributed File System environments for which you are not following Microsoft’s best practices.

Use file-level protection.

VMs for which you would like to exclude volumes or large numbers of files when running backups.

Use file-level protection and exclude files from backups. (With host-level you can exclude virtual disks only. File-level provides more granular control.)

VMs functioning as large file servers for which you may need to frequently recover files.

Use file-level protection so you can search for files to recover by name.

Windows VMs that you would like to protect with Windows replicas.

Use file-level protection.