Creating deduplicated volumes

Deduplication can be configured with thin-provisioned and compressed volumes in data reduction pools for added capacity savings. Deduplication is a type of data reduction that eliminates duplicate copies of data.

When you create a volume, you can specify to include deduplication with other supported capacity savings methods, like compression and thin-provisioning. Deduplicated volumes must be created in data reduction pools.You cannot include deduplicated volumes in data reduction pools and compressed volumes in standard pools within the same I/O group. The system monitors these restrictions when you are creating volumes and issues errors if these conditions are met. However, if you are creating compressed volumes in data reduction pools, deduplication can be used within the same I/O group. If you have existing volumes in standard pools, you can migrate them to data reduction pools to add deduplication to increase capacity savings for the volume.

Using the management GUI

To create a deduplicated volume in the management GUI, complete these steps:

In the management GUI, select Volumes > Volumes > Create Volumes.
On the Create Volumes page, you can create different types of volumes. The type of volumes that you can create depends on the type of topology that is configured on your system. Select the type of volume that you would like to create.
Enter the following information for the volume:
Pool

Select a data reduction pool from the list. To use deduplication with compressed or thin-provisioned volumes, the volume must be in a data reduction pool. If the volume that is being created has mirrored copies, then each copy must be in a data reduction pool. For HyperSwap volumes, you must specify a data reduction pool for each site in the HyperSwap configuration.

Volume details

Enter the quantity, capacity, and name for the volume or volumes that you are creating.

Capacity savings

Select either None, Thin-provisioning, or Compression. For thin-provisioning or compression, you can also select to use deduplication for the volume that you create. For example, you can create a compressed volume that also uses deduplication to remove duplicate data.
Select either Automatic to have the system automatically select the caching I/O group for the volume or select the name of the I/O group from the list. A deduplicated volume or volume copy can be created in a data reduction pool only if the caching I/O group contain nodes with 32 GB memory installed.
Click Create to create volume or volumes that are not mapped to hosts or Create and Map to select the host to map to the volume.

Using the CLI

To create a deduplicated volume in the command-line interface, you can use the -deduplicated parameter in the following ways:

To create a thin-provisioned volume that uses deduplication, enter the following command:
```
mkvolume -pool storage_pool_name -size 100 -unit gb -iogrp 0 -thin -deduplicated
```
where storage_pool_name is the name to the data reduction pool that the volume is associated with. The pool that is specified with the -pool parameter must be a data reduction pool, otherwise the command fails.
To create a compressed volume that uses deduplication, enter the following command:
```
mkvolume -pool storage_pool_name -size 100 -unit gb -iogrp 0 -compressed -deduplicated
```
where storage_pool_name is the name to the data reduction pool that the volume is associated with. The pool that is specified with the -pool parameter must be a data reduction pool, otherwise the command fails.
To create a mirrored copy of a thin-provisioned volume that uses deduplication, enter the following command:
```
addvolumecopy -pool storage_pool_name -thin -deduplicated volume_name
```
where volume_name is the name of the volume copy that is being created and storage_pool_name is the name to the data reduction pool that the volume is associated with. The pool that is specified with the -pool parameter must be a data reduction pool, otherwise the command fails.
To create a compressed volume that uses deduplication in a HyperSwap topology, enter this command:
```
mkvolume -pool storage_pool_name(site 1):storage_pool_name (site 2) -size 1 -unit tb -compressed -deduplicated
```
where storage_pool_name indicates the data reduction pools at each site. Both pools at each site must be data reduction pools.