Media Patrol - NEC EXPRESS5800 User Manual

3.9 Media Patrol

The media patrol feature provides entire reading for the following target HDDs. Because of
aged deterioration, it may not be possible to detect faults of HDDs until they are accessed. The
media patrol, or routine read and check of data in HDDs, allows such faults to be detected as
soon as possible. Therefore, you can take proper measures early.
- HDDs configuring RAID
- Spare HDDs
If accessing to a HDD occurs during media patrol, the media patrol is paused until the
completion of the access. Accordingly, media patrol hardly degrades the system performance.
Because the media patrol feature checks HDDs in a period of low system load, it may not be
able to advance its processing in a system entered in high load status consistently. Therefore,
use the feature in system environment of comparatively low load such as in the night.
IMPORTANT:
Follow the procedure below to provide media patrol.
1. Click the subsystem (ST EX4650EL) icon in the Tree View.
2. Click the downward arrow at the right end of the Background Activities tab in the
Management Window and then click Start Media Patrol.
3. Click [Start].
Media patrol is scheduled by default to be run at 0:00
a.m. on Wednesday every week just after installation
of WebPAM PRO. Change the schedule to be suit to
the environment you use.
The RAID system does not allow media patrol to be
set in HDDs individually.
Media patrol is not done for HDDs having not been
used to configure a disk array or for HDDs not
specified as spare. Specify unconfigured HDDs to hot
spare.
Media patrol can detect media errors of HDDs early
and only repair HDDs being members of redundant
RAIDs. However, it does not check whether HDDs
are consistent with parity.
The feature can run media patrol of specified HDDs at
the specified time only once (scheduled media patrol
is run periodically every specified start time). Media
patrol is not run consistently.
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