BMR Agent 26.1 supported platforms, requirements and known issues

This page provides the following information for the BMR (Bare Metal Recovery) Agent:

• Supported file systems, disks, and partitions

• Limitations

• Known issues

The BMR Agent is used to recover entire Windows servers from backups created by the Windows Agent. For more information, see Recovering a Windows server.

Supported file systems, disks, and partitions

Supported file systems	NTFS FAT32 for volumes that are required for the boot process
Supported disk layouts	MBR GPT
Supported OEM partitions	0x12 // EISA partition (Compaq) 0x84 // Hibernation partition for laptops 0xA0 // Diagnostic partition on some Hewlett-Packard notebooks 0xDE // Dell partition 0xFE // IBM IML partition

Limitations

• The BMR Agent cannot run on 32-bit hardware.

• Volumes that are encrypted using BitLocker, and were unlocked at the time of backup, are not encrypted when they are recovered and must be re-encrypted, if desired.

• BMR Agent is not supported on VMware ESX 4.x.

• UEFI backups cannot be restored to Generation 1 Hyper-V virtual machines, which do not have support for UEFI.

• The BMR Agent can recover a maximum of 21 volumes from a source (backed up) server to a recovery (destination) server. If existing volumes are preserved on the recovery server, the total of:

  • the number of volumes preserved on the recovery server

    plus

  • the number of volumes recovered from the source server

  can be a maximum of 21 volumes. For example, if you want to preserve 3 volumes on a recovery server, you can recover a maximum of 21-3=18 volumes from the source server.

Known issues

• If you recover a Windows server with a dynamic disk to the AWS cloud, the EC2 instance created for the recovered server might not have enough disk space.
  WORKAROUND: After recovering the Windows server to the AWS cloud, manually create a volume in AWS that is large enough for restoring data from the dynamic disk. Attach the volume to the EC2 instance, and initialize it. You can then restore data from the dynamic disk that was backed up to the new volume.

• When recovering a server with an MBR disk to its original system, if you click the AutoMap button, a message states that the source volume cannot be mapped because there is not enough space available.
  WORKAROUND: Drag the MBR disk to the recovery server manually.

• After you recover a computer that has more than one disk, NTFS disks that do not contain the system partition might be offline. This can occur after a recovery with recovery media for Windows Server 2025 or Windows Server 2022.
  WORKAROUND: Bring the NTFS disks online using the Disk Management utility or diskpart command interpreter in Windows.

• When recovering a system to a Hyper-V destination machine, the order of the destination machine disks in the BMR wizard is sometimes different than the order of the disks in the virtual machine settings.

• Removable USB drives on the source or recovery (destination) server are counted in the number of disks on the system and could prevent the AutoMap feature from being available— even though removable USB drives are not backed up and cannot be used as recovery destinations.
  WORKAROUND: If the AutoMap feature is not available, manually create a recovery plan by dragging volumes from the source to the recovery system. If the removable drive is on the recovery system, remove the drive before the recovery.

• If you try to recover a volume that is formatted with a 2K block size to a disk that has a 4K cluster size, the recovery fails with the following error message: Cluster must be multiplication of the physical sector size.

• When you try to recover to a destination disk with an OEM volume, the recovery may fail with the following message: BMR is not able to get drive letter for mapped volume. Restore cannot proceed further. Please cancel and try again.
  WORKAROUND: Delete all partitions from the destination disk. Change the disk format to GPT and then back to MBR, and then try the restore again.

• When mapping a volume, even if you drag and drop the volume to a larger size destination, you may get the following message: Volume cannot be mapped. The destination is not of the same size.
  WORKAROUND: Right-click the volume, delete the partition on the destination disk, and try again.

• The BMR Agent may not retrieve the drive letter for a mapped volume if you drag and drop a large number of partitions to a GPT disk. The recovery may not proceed further.
  WORKAROUND: Cancel and try again, selecting fewer partitions.