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REDUCE

disk-device-name1 [disk-device-nameN]

REDUCE

disk-device-name1 [disk-device-nameN]

Allows you to remove members from an existing mirrorset.

Format

REDUCE

disk-device-name1 [disk-device-nameN]

Parameters

disk-device-name1

Speciﬁes the name of the NORMAL mirrorset member to be removed.

[disk-device-nameN]

Speciﬁes the name of the second mirrorset member to be removed.

Description

This command allows you to remove members from mirrorsets. For a consistent

copy of a stripeset whose members are mirrorsets, all mirrorsets must be reduced

at the same time with one command. It is similar to the SET mirrorset-container-

name REMOVE=disk-device-name command, except that the nominal number of

members in the mirrorset is decreased by the number of members removed, and

the devices are not placed in the failedset.

Note

Mirrorsets have both a nominal number of members and an actual

number of members. The nominal number of members in a mirrorset is

the number given in the SET mirrorset-name MEMBERSHIP=number-of-

members command. If devices have not been added to the mirrorset, or if

a member is removed, the actual number of members may be less than

the nominal number. The actual number of members can never be greater

than the nominal number of members.

The disk devices to be removed need not be members of the same mirrorset.

The devices MUST be part of the same unit (for example, the same stripeset).

This is an atomic operation because the I/O to the unit associated with the given

mirrorset members is stalled while the speciﬁed mirrorset members are removed.

No autosparing occurs, and each mirrorset membership is set to the new reduced

number of members. The removed devices speciﬁed by disk-device-name1 through

disk-device-nameN are not placed in the failedset, but are left as unused devices.

Note that for each mirrorset that you reduce, the mirrorset must have at least

one remaining NORMAL member after the reduction. If this is not true for all

disk-devices-names speciﬁed, then none of the speciﬁed mirrorsets are reduced.

Note

A NORMAL member is a mirrorset member whose entire contents are

guaranteed to be the same as all other NORMAL members. All NORMAL

members have exactly the same contents.

Command Line Interpreter B–45