Acronis Backup for Linux Server - User Guide - Manual (Page 26)

26 Copyright © Acronis International GmbH, 2002-2014
This option is useful in the following cases:

When some data on the volume was lost, but no hard disks were replaced.

When recovering a logical volume over a basic disk or volume. You can resize the resulting
volume in this case.
A system, recovered from a logical volume backup to a basic disk, cannot boot because its kernel tries
to mount the root file system at the logical volume. To boot the system, change the loader
configuration and /etc/fstab so that LVM is not used and reactivate your boot loader (p. 108).

When recovering a basic or logical volume to an existing logical volume.
If the boot partition (/boot) was located on a basic volume, we recommend recovering it to a basic
volume, even if your boot loader supports booting from logical volumes.

Recovering both the structure of logical volumes and their contents.
Such is the case when recovering on bare metal or on a machine with different volume structure.
The structure of logical volumes can be automatically created at the time of recovery (p. 28).
This option is available only under bootable media.
For detailed instructions on how to recover logical volumes, see Recovering MD devices and logical
volumes (p. 27).
3.6.2 Backing up MD devices
MD devices, known as Linux Software RAID, combine several volumes and make solid block devices
(/dev/md0, /dev/md1, ..., /dev/md31). The information about MD devices is stored in /etc/raidtab
or in dedicated areas of those volumes.
You can back up active (mounted) MD devices in the same way as logical volumes. The MD devices
appear at the end of the list of volumes available for backup. If you select MD devices for backup, the
structure of the MD devices will be backed up along with their contents.
Backing up volumes included in MD devices does not make sense when an MD device is mounted, as
it won’t be possible to recover them.
When recovering MD devices under bootable media, the structure of MD devices can be recreated
automatically. For detailed information about recovering MD devices under bootable media, see
Recovering MD devices and logical volumes (p. 27).
For information about assembling MD devices when performing recovery in Linux, see Assembling
MD devices for recovery (Linux) (p. 27).
3.6.3 Backing up hardware RAID arrays (Linux)
Hardware RAID arrays under Linux combine several physical drives to create a single partitionable
disk. The special file related to a hardware RAID array is usually located in /dev/ataraid. You can back
up hardware RAID arrays in the same way as ordinary hard disks.
Physical drives that are part of hardware RAID arrays may be listed alongside other disks as if they
had a bad partition table or no partition table at all. Backing up such disks does not make sense as it
won’t be possible to recover them.