I would like to explore the requirements of expanding
RAID 0,4, and 5 levels from an existing configuration.
For example, if you have 3 disks in a RAID 5 configuration,
you currently cannot add a disk to the RAID 5 without
destructively remaking the RAID 5 configuration and reformatting
the multiple block device upon completion. Is anyone
working on (I remember it mentioned previously on the list)
what has been called "resize array" in the software RAID
howto in the wish list section.
from RAID 5 FAQ:
2.Q: Can I add disks to a RAID-5 array?
A: Currently, (September 1997) no, not without erasing all data.
A conversion utility to allow this does not yet exist. The problem
is that the actual structure and layout of a RAID-5 array depends
on the number of disks in the array. Of course, one can add
drives by backing up the array to tape, deleting all data, creating
a new array, and restoring from tape.
thanks,
Scott
