addvolumecopy

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Use the addvolumecopy command to add a copy to an existing volume. On a standard topology system, you will use this command to add a mirrored copy to an existing volume.

Syntax

Parameters

-pool storage_pool_id | storage_pool_name: (Required) Specifies the storage pool in which to create the new volume copy.
-image mdisk_id | mdisk_name: (Optional) Specifies that the volume copy is to be created (on any topology) in image mode and it specifies which currently unused MDisk to use.
-thin: (Optional) Specifies that the volume copy is to be created with thin provisioning. You cannot specify this parameter with -compressed. If you are adding a volume to a pool that uses a provisioning policy, this parameter is not enabled.
Note: If you do not specify either -thin or -compressed parameters, the system creates a standard-provisioned volume copy.
-compressed: (Optional) Specifies that the volume copy is to be created compressed. You cannot specify this parameter with -thin. If you are adding a volume to a pool that uses a provisioning policy, this value is disabled.
-buffersize buffer_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. If you are adding a volume to a pool that uses a provisioning policy, this parameter uses the default value of 2%.
-warning warning_capacity | warning_percentage%: (Optional) Specifies a threshold at which a warning error log is generated for the volume copy. A warning is generated when the used disk capacity on the thin-provisioned or compressed copy exceeds the specified threshold. You can specify the threshold by using warning_capacity to specify a size, which defaults to MB unless the -unit parameter is specified.If you are adding a volume to a pool that uses a provisioning policy, this parameter uses the default value of 80%.
Important: You can also specify a warning_percentage% to use a percentage of the volume size. If you do not specify a warning threshold, a default value of 80% is used. To disable warnings, specify 0.

You must specify either -thin or -compressed with this parameter.
-unit b | kb | mb | gb | tb | pb: (Optional) Specifies the data units for the buffer_size and -warning parameters.
-noautoexpand: (Optional) Specifies that the volume copy not automatically expand as it is written to; the available buffer capacity decreases as the used capacity increases. The copy goes offline if the buffer capacity is consumed.
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 this keyword, the copy automatically expands as it is written to.
If you are adding a volume to a pool that uses a provisioning policy, the volume automatically expands as it is written to.
-autodelete: (Optional) Specifies that the source volume is deleted after the new volume copy is synchronized.
Restriction: Do not apply the -autodelete for HyperSwap® volume.
-grainsize 32 | 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.
-allowmismatchedscsiids: (Optional) When you create a HyperSwap volume, this parameter allows the primary volume to have different SCSI LUN IDs in the assigned access I/O groups.
volume_id | volume_name: (Required) Specifies the volume to add the volume copy to.

Description

Use the addvolumecopy command to add a copy to an existing volume. The new volume copy is synchronized with the current copy.

When you create a volume copy in a storage pool with a provisioning policy, some parameters will use default settings or the settings from the provisioning policy.

The -autodelete parameter deletes the source volume when the new volume copy is synchronized.

Restriction: You cannot use -autodelete parameter when adding a HyperSwap volume copy.

A volume cannot have volume copies in different storage pools if Cloud Backup is enabled on the volume.

On some node types, you can create a compressed volume copy in a data reduction storage pool for an I/O group. A compressed volume copy in a data reduction pool can only be created in an I/O group with V5030, V7000, or SVC node types. You can source create thin-provisioned volume copies on any node type. Volumes can also have standard-provisioned volume copies in data reduction storage pools.

You cannot specify buffer_size if the volume copy is created in a data reduction storage pool. Specify -thin or -compressed to enable thin provisioning or compression.

You cannot specify -noautoexpand when you create thin-provisioned or compressed volume copies from a data reduction storage pool.

You cannot create a volume copy that is a thin-provisioned or compressed volume in a data reduction storage pool, and the volume caching mode is none or readonly. You must specify chvdisk to change the volume caching mode to readwrite.

You cannot specify -warning for a thin-provisioned or compressed volume copy in a data reduction storage pool.

You cannot specify grain_size for thin-provisioned and compressed volume copies in data reduction storage pools. This type of volume copy is created with a size of 8 KB.

Thin-provisioned or compressed volume copies in data reduction pools cannot be created if the data reduction storage pool is offline and requires recovery. If the recovery is still in progress, you must wait until the recovery is complete and the pool is in online state.

On a standard topology system, you can use this command to add a mirrored copy to an existing volume.

A volume copy cannot be created in the same site as an existing copy of the volume. This command automatically adds the caching I/O group to the access I/O group set of the volume.

When you create a HyperSwap volume, the system attempts to assign the same SCSI LUN ID for the primary volume in all access I/O groups. If an identical SCSI LUN ID is not available in all access I/O groups, the command fails. Use the -allowmismatchedscsiids parameter to allow the system to allocate non-identical SCSI LUN IDs in the access I/O groups. The lowest value available in each access I/O group is used. It might not be the same in all access I/O groups. Make sure that the host supports this configuration.

Failure Scenarios

The following failure scenarios can occur when the command fails:

Scenario 1:

The command fails because of insufficient resources if the I/O group contains any of the following elements:

At least one 8 GiB node.
At least one thin-provisioned or compressed volume in a data reduction pool.
A FlashCopy bitmap size for I/O group exceeds 1.5 GiB.

Scenario 2:

When a thin-provisioned or compressed volume is created within a data reduction pool, the pool must have enough capacity to create more volumes that track SCSI unmap operations from the host. If this capacity is not available, the command fails.

Scenario 3:

Volumes cannot be created in a data reduction pool if offline thin-provisioned or compressed volumes exist in a data reduction pool, either because of thin provisioning (an out-of-space or data corruption issue), or a component that is associated with the thin provisioning keeping a pool volume offline.