Limitations on Hyper-V backup operations

Limitations that apply to all Hyper-V backups

You cannot run concurrent backup or restore operations on the same host. For example, if you run two or more backup vm or restore vm commands on the same host at the same time, one of the backup or restore operations fails with an error message. Starting in Data Protection for Microsoft Hyper-V Version 8.1.6, the Data Protection for Microsoft Hyper-V Management Console will queue up backup and restore tasks that are submitted to the same host. Only one backup or restore task will be active on a host, and additional backup or restore tasks will be in the pending state until the active task completes. At that time, the next pending task will become active.

Data Protection for Microsoft Hyper-V supports incremental-forever full backup and incremental-forever incremental backup operations for Microsoft Hyper-V virtual machines (VMs) in VHDX disk format only. If you need to back up Hyper-V VMs in VHD disk format, use the Version 7.1 backup-archive client (without Data Protection for Microsoft Hyper-V) to create an image backup of the full VM. Issue the V7.1 backup-archive client command dsmc backup vm vmname -vmbackuptype=hypervfull -mode=full to create an image backup of all objects on a Microsoft Hyper-V virtual machine VHD or VHDX disk. Optionally, convert .vhd files to .vhdx format according to instructions available in Microsoft documentation.

Data Protection for Microsoft Hyper-V support for VM backup operations is limited to VM names and Hyper-V host or cluster names that contain English 7-bit ASCII characters only. VM names and Hyper-V host or cluster names that use other language characters are not currently supported. More character restrictions are listed in Unsupported characters in virtual machine and Hyper-V host or cluster names.

The Microsoft Windows Management Instrumentation (WMI) Service (winmgmt) must be running on the systems where Data Protection for Microsoft Hyper-V, IBM Spectrum Protect™ backup-archive client, and IBM Spectrum Protect recovery agent are installed. Operations fail if the WMI Service is not running. Therefore, do not turn off the WMI Service.

Verify that no Exchange Server database is hosted on raw device mapped (RDM) disks in physical compatibility mode, independent disks, or on disks that are attached directly to the guest through in-guest iSCSI.

You cannot back up a VM with a shared virtual hard disk.

Snapshot differential backup operations are not supported in the Hyper-V environment. You cannot run snapshot differential backup operations of a file system that resides on a NetApp filer on a host where the Data Protection for Microsoft Hyper-V data mover is also installed.

Limitations that apply only to VM backups on Windows Server 2012 and 2012 R2

Data Protection for Microsoft Hyper-V does not back up VMs with attached physical disks (pass-through disks such as iSCSI disks). This limitation occurs because Data Protection for Microsoft Hyper-V uses Volume Shadow Copy Service (VSS) for backup operations and VSS cannot create a snapshot of the physical disks. If you try to back up a VM with attached physical disks, the backup operation of the VM with the physical disk fails, but backup operations continue for other VMs.

Hyper-V configurations on the Windows Server 2012 R2 operating system are not compatible with Windows Server 2012. As a result, a restore operation from Windows Server 2012 R2 to Windows Server 2012 fails. However, a restore operation from Windows Server 2012 to Windows Server 2012 R2 succeeds. For more information, got to the Microsoft Knowledge Base and search for Article 2868279.

Limitations that apply only to VM backups on Windows Server 2016 and later

You cannot run a VM backup operation during a rolling upgrade of a Hyper-V cluster operating system.

If Data Protection for Microsoft Hyper-V is unable to retrieve the change tracking information, an incremental-forever full backup is run.

INCLUDE.VMSNAPSHOTATTEMPTS VM_name 1 1

For Windows Serer 2016 only: You cannot install Data Protection for Microsoft Hyper-V on Nano Server for Windows Server 2016. However, you can use Data Protection for Microsoft Hyper-V on Windows Server 2016 to create crash-consistent backups of Nano Server guest VMs.

For late-breaking updates about known issues and limitations, see technote 1993768.