mklvcopy

mklvcopy Command



Purpose

Provides copies of data within the logical volume.

Syntax

mklvcopy [ -a Position ] [ -e Range ] [ -k ] [ -m MapFile 
] [ -s Strict ] [ -u UpperBound ] LogicalVolume Copies [ PhysicalVolume
... ]

Description

The mklvcopy command increases the number of copies in each logical
partition in LogicalVolume. This is accomplished by increasing the
total number of physical partitions for each logical partition to
the number represented by Copies. The LogicalVolume parameter can
be a logical volume name or logical volume ID. You can request that
the physical partitions for the new copies be allocated on specific
physical volumes (within the volume group) with the PhysicalVolume
parameter; otherwise, all the physical volumes within the volume group
are available for allocation.

The logical volume modified with this command uses the Copies parameter
as its new copy characteristic. The data in the new copies are not
synchronized until one of the following occurs: the -k option is used,
the volume group is activated by the varyonvg command, or the volume
group or logical volume is synchronized explicitly by the syncvg command.
Individual logical partitions are always updated as they are written
to.

The default allocation policy is to use minimum numbering of physical
volumes per logical volume copy, to place the physical partitions
belong to a copy as contiguously as possible, and then to place the
physical partitions in the desired region specified by the -a flag.
Also, by default, each copy of a logical partition is placed on a
separate physical volume.

Notes: 

1.	This command fails on a striped logical volume, mirroring is not
possible.

2.	To use this command,  either have root user authority or
be a member of the system group.

You can use the System Management Interface Tool (SMIT) to run this
command. To use SMIT, enter:

smit mklvcopy

Flags

-a Position	Sets the intra-physical volume allocation policy (the
position of the logical partitions on the physical volume). The Position
variable can be one of the following:

m	Allocates logical partitions in the outer middle section of each
physical volume. This is the default position.

c	Allocates logical partitions in the center section of each physical
volume.

e	Allocates logical partitions in the outer edge section of each physical
volume.

ie	Allocated logical partitions in the inner edge section of each
physical volume.

im	Allocates logical partitions in the inner middle section of each
physical volume.

-e Range	Sets the inter-physical volume allocation policy (the number
of physical volumes to extend across, using the volumes that provide
the best allocation). The Range value is limited by the Upperbound
variable (set with the -u flag), and can be one of the following:

x	Allocates across the maximum number of physical volumes.

m	Allocates logical partitions across the minimum number of physical
volumes. This is the default for the -e flag.

-k	Synchronizes data in the new partitions.

-m MapFile	Specifies the exact physical partitions to allocate. Partitions
are used in the order given by the file designated by the MapFile
parameter. Used partitions in the file are skipped. All physical partitions
belonging to a copy are allocated before allocating for the next copy.
The MapFile format is:

PVname:PPnum1[-PPnum2]

where PVname is a physical volume name (for example, hdisk0). It is
one record per physical partition or a range of consecutive physical
partitions.

PVname	Name of the physical volume as specified by the system.

PPnum	Physical partition number. Physical partition numbers can range
from 1 to 1016.

-s Strict	Determines the strict allocation policy. Copies of a logical
partition can be allocated to share or not to share the same physical
volume. The Strict variable can be one of the following:

y	Sets a strict allocation policy, so copies for a logical partition
cannot share the same physical volume. This is the default for the
-s flag.

n	Does not set a strict allocation policy, so copies for a logical
partition can share the same physical volume.

-u UpperBound	Sets the maximum number of physical volumes for new
allocation. The value must be between one and the total number of
physical volumes. The default is the total number of physical volumes
in the volume group.

Example

To add physical partitions to the logical partitions in the logical
volume lv01, so that a total of three copies exists for each logical
partition, enter:

mklvcopy lv01 3

The logical partitions in the logical volume represented by directory
lv01 have three copies.

Files

/usr/sbin/mklvcopy	Contains the mklvcopy command.

Related Information

The chlv command, lslv command, mklv command, syncvg command, varyonvg
command.

The Logical Volume Storage Overview in AIX Version 4 System Management
Guide: Operating System and Devices.

The System Management Interface Tool (SMIT): Overview in AIX Version
4 System Management Guide: Operating System and Devices.