Parity Checking; Raid And Jbod Types - Maxtor NAS 6000 Administration Manual

MaxAttach NAS 6000 Administration Guide

Parity Checking

Parity checking is creating a parity check sum for the writes to drives in an array, and then
writing the parity information to a dedicated parity drive (called dedicated parity) or
writing the parity information as the next striped data block to the next drive in the
array.separate data block (called distributed parity). The parity check sum allows the system
to recover missing data in the event of the failure of a single member of RAID array.
By combining these techniques in various combinations, different system capabilities are
provided to met a users unique local needs.

RAID and JBOD Types

The common RAID types are as follows and all area available to most user data drives on
the NAS 6000:
RAID 0 - Striping
n
RAID 1 - Mirroring
n
RAID 0+1 - Mirrored sets of Striped Disks
n
RAID 5 - Striped Disks with Parity Check
n
JBOD - An additional non-RAID option for single disk control, also called Just a
n
Bunch Of Disks
Chapter #11 - Appendix - Disk Array RAID Concepts
11/07/01 -- Revision 2.0.03A
Chapter #11 - Appendix - Disk Array RAID Concepts
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Key RAID Technical Methods
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