What is the difference between a volume and a disk?

[Vinnster]

In reading about snapclones and and snapshots there seems to be different definitions volume and virtual disks.

At times it seems people use the interchangeably when I though a volume could be part of a disk or span multiple disks.

I am confused.

[IBaltay]

Hi, it seems to be only a wording problem and it differs from the storage to the storage so I will try you confuse you even more :-)

in EVA the term virtual disk is equal to the logical volume (acrooss the physical disks in the Disk group)
in XP the term logical device is equal to the logical volume (across the physical disks in the Parity/Array group)
in host LVM the term physical volume could bee EVA logical volume or XP logical device and it is in the role of the physical disk.
in host LVM the term logical volume is created across the physical volumes in the volume group.

Resume:
the word disk is close to the physical disk itself.
the word volume is close to the logical disk.

[Vinnster]

Thank you very much. That helps and now I know I am not going crazy.

[Uwe Zessin]

Ha! Wait until you have to deal with the next product or another vendor...

By the way, the term 'volume' is also used to describe a file system structure.