Digital Equipment HSZ40, Справочное руководство

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MIRROR 2–45
HSZ40 Array Controller CLI Reference Manual
The
COPY
switch allows you to set the speed at which the controller copies data from
normal mirrorset members to new members.
Select
NORMAL
to prioritize other controller operations over the copy operation. The
controller uses relatively few resources to perform the copy, and there is little impact on
performance.
Select
FAST
when the copy operation must take precedence over other controller
operations. The controller uses more resources and the copy takes less time, but overall
controller performance is reduced during the copy.
POLICY=BEST_FIT
POLICY=BEST_PERFORMANCE
NOPOLICY (Default)
Specifies the replacement policy to be used when a mirrorset member fails.
Select
BEST
_
FIT
to choose a replacement device from the spareset that most closely
matches the capacities of the remaining members. If more than one device in the spareset
is the correct size, the controller selects the device that gives the best performance.
Select
BEST
_
PERFORMANCE
to choose a replacement device from the spareset that results in
the best performance (the device should be on a different port than existing members). If
more than one device in the spareset has the best performance, the controller selects the
device that most closely matches the size of the remaining members.
Select
NOPOLICY
to prevent the controller from replacing a failed disk drive. This causes
the mirrorset to run with less than the nominal number of members until a
BEST
_
FIT
or
BEST
_
PERFORMANCE
policy is selected, or a member is manually replaced in the mirrorset.
Examples
The commands in this example create a one-member mirrorset from each member of a
stripeset. The succeeding commands set the nominal number of members in each mirrorset
to two and add a second disk to each mirrorset. Note that you do not need to initialize the
mirrorsets or add them as units; the higher-level structure of the stripeset is carried down
to the mirrorsets.
CLI> ADD DISK DISK110 1 1 0
CLI> ADD DISK DISK210 2 1 0
CLI> ADD DISK DISK310 3 1 0
CLI> ADD STRIPESET STRIPE1 DISK110 DISK210 DISK310
LI> INITIALIZE STRIPE1
CLI> ADD UNIT D102 STRIPE1
CLI> MIRROR DISK110 MIRROR1
CLI> SET MIRROR1 MEMBERSHIP=2
CLI> SET MIRROR1 REPLACE=DISK220