Expanding volumes by using the CLI

You can use the command-line interface (CLI) to expand a volume on Windows, AIX®, or Linux® systems.

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Volumes that are mapped for FlashCopy® cannot be expanded.

Run Windows Update and apply all recommended updates to your system before you attempt to expand a volume that is mapped to a Windows host.

Determine the exact size of the source or master volume. To do so, issue the following CLI command, where vdiskname is the name of the volume for which you want to determine the exact size.
lsvdisk -bytes vdiskname

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

You can expand volumes for the following reasons:
  • To increase the available capacity on a particular volume that is already mapped to a host.
  • To increase the size of a volume so that it matches the size of the source or master volume, and so that it can be used in a FlashCopy mapping or Metro Mirror relationship.

You cannot expand the capacity of any volume in a Global Mirror with change volumes relationship or in a HyperSwap® relationship.

You can expand the capacity of volumes in Metro Mirror and Global Mirror relationships that are in consistent_synchronized state. You cannot expand the following types of volumes:
  • Volumes in HyperSwap relationships or in Global Mirror relationships that are operating in cycling mode.
  • Volumes in relationships where a change volume is configured.
  • Mirrored volumes that have at least one fully allocated copy.

You must expand both volumes in a relationship to maintain full operation of the system. Expand the secondary volume by the required capacity, and then expand the primary volume.

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

For more information about restrictions on expanding volumes, see the software restrictions page on the following website: www.ibm.com/support.