Use of the mkvdisk  command to create an image-mode volume, is shown in Example 7-5. 

IBM_2145:ITSO_CLUSTER:superuser>mkvdisk -mdiskgrp ITSO_Pool1 -iogrp 0 -mdisk mdisk25 -vtype image -name Image_Volume_A Virtual Disk, id [6], successfully created 

This example creates an image-mode volume named Image_Volume_A  that uses the mdisk25 MDisk. The MDisk is moved to the storage pool ITSO_Pool1 , and the volume is owned by the I/O Group io_grp0 . 

If you run the  lsvdisk command, it shows volume that is named Image_Volume_A with type image, as shown in Example 7-6. 

IBM_2145:ITSO_CLUSTER:superuser>lsvdisk -filtervalue type=image id name IO_group_id IO_group_name status mdisk_grp_id mdisk_grp_name capacity type FC_id FC_name RC_id RC_name vdisk_UID fc_map_count copy_count fast_write_state se_copy_count RC_change compressed_copy_count parent_mdisk_grp_id parent_mdisk_grp_name formatting encrypt volume_id volume_name function 6 Image_Volume_A 0 io_grp0 online 5 ITSO_Pool1 1.00GB image 6005076801FE80840800000000000021 0 1 empty 0 no 0 5 ITSO_Pool1 no no 6 Image_Volume_A 

## 7.9.5 Adding a volume copy 

You can add a copy to a volume. Consider the case where volume copies are defined on different MDisks. In this case, the volume remains accessible even when the MDisk on which one of its copies depends becomes unavailable. You can also create a copy of a volume on a dedicated MDisk by creating an image mode copy of the volume. Notice that while volume copies can increase the availability of data, they are not separate objects. 

Volume mirroring can be also used as an alternative method of migrating volumes between storage pools. 

Use the addvdiskcopy  command to create a new copy of a volume. This command creates a copy of the chosen volume in the specified storage pool, which changes a non-mirrored volume into a mirrored one. 

The following scenario shows how to create a new copy of a volume in a different storage pool. As you can see in Example 7-7, the volume initially has a single copy with copy_id 0  that is provisioned in the Pool0  pool. 

IBM_Storwize:ITSO:superuser>lsvdisk 2 id 2 name vdisk0 IO_group_id 0 IO_group_name io_grp0 status online mdisk_grp_id 0 mdisk_grp_name Pool0 capacity 10.00GB type striped 

