Image mode thin-provisioned volumes

When you create an image mode volume, you can designate it as thin-provisioned. An image mode thin-provisioned volume has a virtual capacity and a real capacity.

An image mode thin-provisionedvolume has a direct relationship with a single MDisk where the contents of the MDisk map to the real capacity that is used by the thin-provisionedvolume. Unlike fully allocated volumes, the logical block address (LBA) on the MDisk is not necessarily the same as the LBA on the volume. You cannot change the real capacity of an image mode thin-provisionedvolume manually or by using the autoexpand feature. To use the autoexpand feature, the volume must be in managed mode.

You can use an image mode volume to move a thin-provisionedvolume between two Lenovo Storage V seriesclustered systems by using the following procedure. The procedure is similar to that used for fully allocated volumes, but has an extra step during the import process to specify the existing thin-provisioned metadata, rather than to create a new, empty volume.

If the volume is not already in image mode, migrate the volume to image mode and wait for the migration to complete.
Delete the volume from the exporting system.
Disconnect the MDisk from the exporting system and connect the MDisk to the importing system.
Create a new image mode thin-provisionedvolume using the MDisk. You must specify the import option.
Optionally, migrate the volume to managed mode.

The import option is valid only for Lenovo Storage V seriesthin-provisionedvolumes. If you use this method to import a thin-provisioned volume that is created by RAID storage systems into a clustered system, Lenovo Storage V series cannot detect it as a thin-provisionedvolume. However, you can use the volume mirroring feature to convert an image-mode fully allocated volume to a thin-provisionedvolume.