Choosing the Right Disk Technology in a High Availability Environment DRAFT Version 2.0, August 1996

Table M: Disk Selection Matrix by Technology
Technology Criterion If Required, then If Not a
choose from Requirement,
this list of then choose
options from this list
DRAFT -- Revision 2.0
August 22, 1996Page 51
data redundancy
3-way full protection LVM mirrored N/A
2-way full protection LVM mirrored
parity protection RAID 3 or 5
or RAID 0/1
lowest cost LVM mirrored
RAID 5 HADA or
AutoRAID
smallest footprint RAID 0/1
RAID 5 HADA or
AutoRAID
LVM mirrored
No Single Points of Failure (SPOFs) RAID 0/1, 1
LVM mirrored,
HASS,
AutoRAID,
Symmetrix
RAID 5 HADA
(except power)
RAID 3
RAID 5
capacity > mirrored standalone capacity any
RAID 5 HADA,
AutoRAID,
Symmetrix
backup from offline snapshot any
LVM mirrored
greatest general performance any
LVM mirrored
greatest absolute performance solid state disks any
power source redundancy any
LVM mirrored
total disk cable length > 25 m F/W SCSI
FC/SCSI Mux
Table N shows which products meet the decision criteria discussed above. The column
codes refer to the following products:
A - standalone LVM mirrored disks
B - High Availability Storage System (HASS) using LVM mirroring