Use the mkvolume command to create an
empty volume from existing storage pools. You can use this command
for high availability configurations that include HyperSwap®,
but it can also be used for volumes that are not high availability.
Syntax
mkvolume [ namename ] sizedisk_size [ -unit { b | kb | mb | gb | tb | pb } ] [ -iogrp { iogroup_id | iogroup_name } ] -pool { storage_pool_id | storage_pool_name } [ -cache { none | readonly | readwrite } ] [ { -thin | -compressed } ] [ -buffersize { buffer_size | buffer_percentage% } ] [ -warning { warning_capacity | warning_percentage% } ] [ -noautoexpand ] [ -grainsize { 32 | 64 | 128 | 256 } ] [ -udidudid ]
Parameters
- -namename
- (Optional) Specifies the name that is used for the volume that
is created. This value must be an alphanumeric string 1 - 63 characters.
Remember: If you do not specify -name,
a unique default name such as volume1 is used.
- -sizedisk_size
- (Required) Specifies the capacity of the volume, which is used
with the value of the unit. The default capacity is in MB. When the
unit of bytes is used, all capacities must be in multiples of 512
bytes. An entire extent is reserved even if it is only partially used.
- -unitb | kb | mb | gb |
tb | pb
- (Optional) Specifies the data units to use with the capacity that
is specified by the -size parameter. The default
unit type is mb.
- -iogrpiogroup_id_list |
iogroup_name_list
- (Optional) Specifies the I/O group that the new volume is cached
in. The value can be a colon-separated list of up to two I/O group
IDs or names. If no value is specified, the caching I/O group is selected
based on the storage pool site. If you do not specify the -iogrp parameter,
the caching I/O group is selected by the system.
Important: If
two I/O groups are specified, they must be in different sites, and
the storage pools that are specified must be in different sites. The
order of the sites must correspond.
If you create a HyperSwap volume,
the caching I/O groups are selected based on the sites of the storage
pools.
- -poolstorage_pool_id_list
| storage_pool_name_list
- (Required) Specifies the storage pool in which to create the new
volume. The value must be a colon-separated list of up to two storage
pool IDs or names.
Note: If one storage pool is specified, a basic
volume is created with one copy.
On systems with standard topology,
a mirrored volume can be created by specifying two storage pools.
On systems
with a hyperswap topology, a highly available volume
can be created by specifying two storage pools in different sites.
- -cachenone | readonly |
readwrite
- (Optional) Specifies the caching options for the volume. Use one
of the following valid entries:
- readwrite enables the cache for the volume (default)
- readonly disables write caching but allows read
caching for a volume
- none disables the cache mode for the volume
- -thin
- (Optional) Specifies that the volume is to be created with thin-provisioning.
You cannot specify this parameter with -compressed.
If you do not specify -thin or -compressed,
the volume that is created is fully allocated.
- -compressed
- (Optional) Specifies that the volume is to be created compressed.
If the -iogrp parameter is not specified, the least
used I/O group is used for compressed copies (considering the subset
of I/O groups that support compression).
Remember: This
command fails if no I/O groups support compression. If there are two
sites, both sites must have at least one I/O group that supports compression.
You
cannot specify this parameter with -thin. If
you do not specify -thin or -compressed,
the volume that is created is fully allocated.
- -buffersizebuffer_size
| buffer_percentage
- (Optional) Specifies the pool capacity the volume attempts to
reserve as a buffer for thin-provisioned and compressed volumes. You
must specify either -thin or -compressed with
this parameter. The default value is 2%.
- -warningwarning_capacity
| warning_percentage
- (Optional) Specifies a threshold at which a warning error log
is generated for volumes. A warning is generated when the used disk
capacity on the thin-provisioned volume exceeds the specified threshold.
You must specify either -thin or -compressed with
this parameter. The default value is 80%.
- -noautoexpand
- (Optional) Specifies that the volume not automatically expand
as it is written to. The available buffer capacity decreases as the
used capacity increases. The volume copy goes offline if the buffer
capacity is fully used. The buffer capacity can be increased by specifying expandvdisksize
-rsize. You must specify either -thin or -compressed with
this parameter. If you do not specify -noautoexpand,
the volume automatically expands as it is written to.
- -grainsize32 | 64 | 128
| 256
- (Optional) Sets the grain size (KB) for a thin-provisioned volume.
If you are using the thin-provisioned volume in a FlashCopy map, use the same grain size
as the map grain size for best performance. If you are using the thin-provisioned
volume directly with a host system, use a small grain size. The grain
size value must be 32, 64, 128,
or 256 KB. The default is 256 KB.
- -udidudid
- (Optional) Specifies the unit number udid for
the volume.
Important: The udid is an
identifier that is required to support OpenVMS hosts (no other systems
use this parameter).
Valid options are a decimal number from 0 through 32767,
or a hexadecimal number from 0 through 0x7FFF.
A hexadecimal number must be preceded by 0x (for
example, 0x1234).
Description
This
command creates an empty volume, which is a formatted (zeroed) volume,
by using storage from existing storage pools. You can also create a highly available
volume on systems with hyperswap topology.
Use the mkimagevolume command to create
a new volume by importing existing data on a managed disk.
An invocation example to create a volume in storage
pool 0
mkvolume -pool 0 -size 1000
The
detailed resulting output:
Volume, id [0], successfully created.
An invocation
example to create a HyperSwap volume
with a hyperswap topology
mkvolume -pool site1pool:site2pool -size 200
The
detailed resulting output:
Volume, id [2], successfully created.