Expanding VDisks

You can use the command-line interface (CLI) or the SAN Volume Controller Console to expand a virtual disk (VDisk).

VDisks that are mapped for FlashCopy® or that are in Metro Mirror relationships cannot be expanded.

Ensure that you have run Windows® Update and have applied all recommended updates to your system before you attempt to expand a VDisk that is mapped to a Windows host.

Determine the exact size of the source or master VDisk by issuing the following CLI command:

svcinfo lsvdisk -bytes vdiskname

where vdiskname is the name of the VDisk for which you want to determine the exact size.

VDisks can be expanded under Windows concurrently with I/O operations.

You can expand VDisks for the following reasons:

To increase the available capacity on a particular VDisk that is already mapped to a host.
To increase the size of a VDisk so that it matches the size of the source or master VDisk and so that it can be used in a FlashCopy mapping or Metro Mirror relationship.

A VDisk that is not mapped to any hosts and does not contain any data can be expanded at any time. If the VDisk contains data that is in use, you can expand the VDisks if your host has a supported AIX® or Microsoft® Windows operating system.

The following table provides the supported operating systems and requirements for expanding VDisks that contain data:

Operating system	Supported	Requirement
AIX	Yes	AIX version 5.2 or later
HP-UX	No	-
Linux®	No	-
SUN Solaris	No	-
Microsoft Windows NT®	No	-
Microsoft Windows	Yes	Windows version 2000 or later