Chapter 7. Volumes 293
You must use the -mdisk parameter to specify an MDisk that has a mode of unmanaged. The 
-fmtdisk parameter cannot be used to create an image mode volume.
Use of the mkvdisk command to create an image mode volume is shown in Example 7-5.
Example 7-5   The mkvdisk (image mode) command 
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
As shown in this example, an image mode volume named Image_Volume_A is created 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 named Image_Volume_A with type image, 
as shown in Example 7-6.
Example 7-6   The lsvdisk command 
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
7.8.5  Adding a volume copy
You can add a copy to a volume. If volume copies are defined on different MDisks, 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. Although 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. 
To create a copy of a volume, use the addvdiskcopy command. This command creates a copy 
of the chosen volume in the specified storage pool, which changes a non-mirrored volume 
into a mirrored one.
Capacity: If you create a mirrored volume from two image mode MDisks without specifying 
a -capacity value, the capacity of the resulting volume is the smaller of the two MDisks. 
The remaining space on the larger MDisk is inaccessible.
If you do not specify the -size parameter when you create an image mode disk, the entire 
MDisk capacity is used.