I have inherited a machine which has 2 physical disks and uses Linux SW RAID(1). Both disks are partitioned and are are all individual arrays (/dev/md0, /dev/md6, etc.). Those arrays are then mounted (/boot, /home, etc. even /tmp).

As RAID is designed to mitigate physical failures, is there any reason why one would use this technique over whole-disk arrays that are then partitioned (perhaps using LVM)? This seems prone to more potential issues, but may have some special properties that I haven't been able to glean.

I'm planning on moving this setup to: disks?SWRAID(1)?LVM as I'll be making multiple VMs out of the one machine, but wanted to make sure I knew what I was doing when I got rid of the old setup.