Promise Technology 2-Year Extended Warranty for VessR2000 RAID Head - Manual (Page 33)

N
otable
F
eatures iN the
V
ess
r2600
These features were introduced in Release 1.0, but mentioned here for users who are new to the Vess R-Series.
P
erfect
r
ebuild
™
The PerfectRebuild™ feature is an innovative approach to rebuilding a RAID array in order to significantly
reduce the amount of time needed for completion. This frees up CPU resources more quickly to be available for
I/O and other demands. PerfectRebuild™ ignores any portion of the logical drive where no write changes have
occurred, focusing only on the parts that have changed. The conventional approach has been to rebuild the
entire logical drive, even sections with no write changes. This reduction in the total time needed for a rebuild is
especially significant for very large drives.
A
dvAnced
b
Attery
f
lAsh
b
AckuP
Use the optional Backup Battery Unit (BBU) and Flash modules for maximum data protection in the event of
power loss. High performance RAID arrays operating in write-back mode present a write loss risk in the event
of a power loss. Since data is considered committed as soon as the controller has received it in cache memory,
it will be lost if power is interrupted. The conventional solution is to use a BBU to maintain the RAID cache for
72 hours. A better solution is to use power from the BBU to write the content of the RAID controller write cache
to non-volatile flash memory in order to extend the period of cache protection beyond the standard 72 hours
provided by a typical BBU.
O
nline
lun c
lOne
This is an improvement upon the previous LUN Clone which required the LUN to be taken offline during the
duration of the process. The Online LUN Clone feature creates a copy of a LUN without stopping I/O on the
source LUN. All data on the source LUN is copied and synchronized in a background operation.
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Vess R2000 Series Product Manual Promise Technologies