You can select either a physical disk or a logical volume as a part of a
copy process. Physical disks correspond to the actual devices in the
machine. Logical volumes are independent of the physical layout to a
certain extent, and refer to the logical data segmentation. For example,
you can have two different logical volumes (partitions) on the same
physical disk. On the other hand, a software RAID or spanned volume
spans across several physical disks.
The logical volume must be
properly mounted (i.e. working to a certain extent), otherwise you can't
create a copy of it. Hence, if you are taking an image of the system for
a later data recovery or for a forensic purpose, it is better to stick
to physical disks (unless complex RAIDing is involved).
Volume locking considerations
Disk copying is the lengthily process. It is required that the drive
contents does not change during copying; otherwise, the resulting image
will be inconsistent. To avoid data changes, the devices involved in
process have to be "locked". Zlon exclusively "locks" the
volume for its own use, so no other program can use the volume
concurrently.
The "lock" is associated with the volume (logical disk).
If a physical disk is being copied, all the volumes it contains have to
be locked. In case the physical disk holds a part of a composite volume
(e.g. part of the software RAID or a stripe set), the entire composite
volume is locked.
There are cases when it is not possible to acquire a volume lock.
These include
Volumes which have an open files or folders on them
System volume (containing the "WINDOWS" folder)
Volume containing the page file
If there is a problem locking a volume, Zlon will
display a warning message. You then can
[Retry] Find the program using the volume and close it, then
retry locking.
[Abort] Retreat back one step and select another device.
[Ignore] Continue without locking. Be advised that the image
will be inconsistent and can't be used for backup purposes. However,
the result is typically satisfactory for a subsequent data recovery.
