Recovering Dynamic Volumes - ACRONIS Backup & Recovery 10 Advanced Server User Manual

Recovering dynamic volumes

A dynamic volume can be recovered
 over any type of existing volume
 to unallocated space of a disk group
 to unallocated space of a basic disk.
Recovery over an existing volume
When a dynamic volume is recovered over an existing volume, either basic or dynamic, the target
volume's data is overwritten with the backup content. The type of target volume (basic,
simple/spanned, striped, mirrored, RAID 0+1, RAID 5) will not change. The target volume size has
to be enough to accommodate the backup content.
Recovery to disk group unallocated space
When a dynamic volume is recovered to disk group unallocated space, both the type and the
content of the resulting volume are recovered. The unallocated space size has to be enough to
accommodate the backup content. The way unallocated space is distributed among the disks is
also important.
Example
Striped volumes consume equal portions of space on each disk.
Assume you are going to recover a 30GB striped volume to a disk group consisting of two
disks. Each disk has volumes and a certain amount of unallocated space. The total size of
unallocated space is 40GB. The recovery will always result in a striped volume if the
unallocated space is distributed evenly among the disks (20GB and 20GB).
If one of the disks has 10GB and the other has 30GB of unallocated space, then the recovery
result depends on the size of the data being recovered.

If the data size is less than 20GB, then one disk can hold, say, 10GB; the other will hold the
remaining 10GB. This way, a striped volume will be created on both disks and 20GB on the
second disk will remain unallocated.

If the data size is more than 20GB, the data cannot be distributed evenly between the two
disks, but can fit into a single simple volume. A simple volume accommodating all the data
will be created on the second disk. The first disk will remain untouched.
Recovered to:
Dynamic volume
Unallocated space (disk group)
Basic MBR volume
Basic GPT volume
Unallocated space (basic MBR disk)
Copyright © Acronis, Inc., 2000-2010
Backed up (source):
Dynamic volume Basic MBR volume
Dynamic volume Dynamic volume
Type as of the Type as of the
target
Dynamic volume Dynamic volume
Type as of the
source
Basic MBR volume Basic MBR volume
Basic GPT volume Basic GPT volume
Basic MBR volume Basic MBR volume
Basic GPT volume
Dynamic volume
Type as of the
target target
N/A
Simple
Basic MBR volume
Basic GPT volume
Basic MBR volume
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