Note

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Hyper-V Backup

Note

Remember to read the Best Practices chapter common for all of our hypervisor plugins.

Bacula Enterprise offers three ways to backup your Hyper-V virtual machines:

Important

The HyperV WinAPI plugin is the newest and most advanced plugin available for backing up Hyper-V environments. It offers the most comprehensive set of features, ensuring seamless integration and efficient backups. Due to its robust functionality and extensive capabilities, this plugin is now the recommended solution for all Hyper-V backup needs.

• Hyper-V WinAPI

The HyperV WinAPI plugin allows for full, differential, and incremental backups of Hyper-V virtual machines, supporting migration of VMs in cluster environments without requiring local snapshots. Single Item Restore is supported.

Warning

The Hyper-V VSS and Hyper-V WMI solutions are older methods for backing up Hyper-V environments. These options are not recommended for use.

• Hyper-V VSS

VSS services enable Bacula Enterprise to do snapshot backup of your Hyper-V virtual machines.

Single Item Restore is supported, but differential and incremental level backup cannot be done using this method.

• Hyper-V WMI

The WMI provider allows you to perform differential and incremental backup for Microsoft Hyper-V. Single Item Restore is not possible using this method.

Hyper-V Plugins to Cover All Backup Needs

Microsoft has created various technologies for backing up Hyper-V virtual machines. Thus, multiple Bacula Plugins have been designed to maximize the benefits of each solution.

Hyper-V is equipped with a VSS writer on all compatible versions of Windows Server. This VSS writer enables developers to utilize the existing VSS infrastructure for backing up virtual machines to Bacula using the Bacula Enterprise VSS Plugins. This technology is supported by the original Bacula Hyper-V plugin. Although it doesn’t allow incremental and differential backups and other more granular VM-based options, it can still cover any Hyper-V version. Therefore, it is highly recommended for small standalone Hyper-V servers (single node, no Failover Cluster) and older Hyper-V versions that do not offer Virtual Disk Service or Hyper-V WMI API.

The Virtual Disk Service (VDS) is a service provided by Microsoft Windows that handles query and configuration tasks upon request from end users, scripts, and applications. This service is compatible with Windows Server 2003, Windows Vista, and newer versions. The Hyper-V Winapi Plugin utilizes this technology to backup and restore virtual machines. It supports incremental and differential backups, making it the recommended solution for more intricate Hyper-V servers, such as Failover Clusters with multiple nodes, where local disk space is a critical resource. Depending on the relocation of virtual machines within the Cluster, it may be necessary to migrate the backed-up VMs across specific nodes.

Starting in Windows 8 and Windows Server 2012, Hyper-V supports backup via the Hyper-V WMI API. This feature enables individual Guest VMs to be backed up separately and incrementally, offering a more scalable solution compared to using VSS in the host. The Bacula Enterprise Hyper-V WMI Plugin uses this technology for backup and restore to/from Bacula. It backups/restores VM in the recommended Microsoft format. By utilizing the Microsoft snapshot format from/to disk, it is essential to have sufficient disk space available for the process to proceed smoothly. In scenarios where disk space may be limited due to busy configurations, the Hyper-V Winapi Plugin can be utilized as an alternative solution.

Backups created using the Hyper-V WMI Plugin, Hyper-V Winapi Plugin and Hyper-V Plugin are not compatible with each other.