Promise Technology 2-Year Extended Warranty for VessR2000 RAID Head - Manual (Page 337)

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Vess R2000 Series Product Manual Promise Technologies
WritePolicy= Used to specify the write policy for the logical drive.
writethru Writes are not cached
writeback Writes are cached
ReadPolicy= Used to specify read policy for the logical drive.
readahead Reads extra data to reduce read times for sequential data.
readcache Caches the reads in case the same request is made again.
nocache No read cache.
parity= Used to specify the method of parity distribution for RAID 5, 50, 6,
and 60.
left Left asymmetric.
right Right asymmetric.
Axle= RAID 50, 3 to 32 drives per axle.
RAID 60, 4 to 32 drives per axle.
Range is 2 to 16 axles.
codec= Used to specify the codec scheme for RAID 6 and 60.
p+q
q+q
PreferredCtrlId= Used to specify which controller the LD is preferred for LUN
affinity. Valid value is 1 or 2. If value is not specified, LUN affinity
will be auto balanced.
PerfectRebuild= Used to specify which logical drives supply to Perfect Rebuild.
enable (Default)The maximum amount of logical drive which support
perfect rebuild is 30. If you select perfectrebuild=enable, only
sectors where write changes occurred are rebuilt.
disable Perfect rebuild will not supply to this logical drive.
-c Specifies the number of arrays to give a summary of when used