topic Re: Dynamic Volume Expansion in Operating System - OpenVMS

Dynamic Volume Expansion

James Powers_1 — Wed, 26 Jul 2006 08:46:50 GMT

How do I determine if Dynamic Volume Expansion has been enabled. My customer does not specify a size and always takes the default of 1TB.

Thank You

Re: Dynamic Volume Expansion

Robert Gezelter — Wed, 26 Jul 2006 09:02:52 GMT

James,

SHOW DEVICE xxx/FULL will show the "Expansion Size Limit". I do note, however, that the status of the Dynamic Extension bit is not displayed.

On one of my 7.3-2 systems, the difference between the current volume size and the expansion limit is negligible (basically rounding caused by the structure of the bitmap).

On a volume that is properly configured for the use of the Dynamic Volume Expansion feature, the difference between volume size and expansion limit should be significant.

- Bob Gezelter, http://www.rlgsc.com

Re: Dynamic Volume Expansion

Volker Halle — Wed, 26 Jul 2006 09:03:17 GMT

James,

welcome to the OpenVMS ITRC forum.

DVE (Dynamic Volume Expansion) has been implemented in OpenVMS Alpha V7.3-2.

It allows you to dynamically expand the Logical Volume size of a publicly mounted disk, if the Expansion Size Limit had been appropriately set before.

$ SHOW DEVICE/FULL will list:

Total blocks - (current) physical size of disk
Logical Volume Size - (current) logical volume size
Expansion Size Limit - maximum Expansion Size

As long as the expansion size limit has not yet been reached, you can use SET VOLUME/SIZE to expand the logical disk volume size up to the current physical size of the disk. And some storage controllers (e.g. EVA) also allow you to expand the physical size of the disk while it's still mounted and in operation.

Volker.

Re: Dynamic Volume Expansion

Ian Miller. — Wed, 26 Jul 2006 09:04:52 GMT

In the display of SHOW DEVICE/FULL if the logical volume size is less that the expansion size limit then potentially the volume can be expanded.

See
http://h71000.www7.hp.com/doc/732FINAL/aa-pv5mh-tk/00/00/89-con.html