The SAN Volume Controller (SVC) is a storage virtualization device that allows customers to combine capacity from multiple heterogeneous storage systems into a single reservoir of storage that can be managed from a central point. Although SVC provides a complete command line interface (CLI), customers have been asking for a means of scripting this interface ever since its original release.

Scripting Tools for SVC extends Perl to provide a powerful and flexible scripting environment and simplifies the automation of complex tasks within SVC. An example script is included along with the core module in order to showcase one such "solution": the rebalancing of the virtualized storage across the underlying storage. This solution allows customers to maximize the use of their underlying storage.

This technology allows customers to easily implement their custom policies and control mechanisms.

Scripting Tools for SVC is compatible with Windows®, Linux®, and other systems (see the Requirements section for details).

How does it work?

SVC Scripting Tools provides a Perl library module, IBM::SVC.pm, that extends the SVC command line interface into the Perl environment. This extension allows customers to write their own Perl scripts for the management and maintenance of SVC. Two example scripts show how to make use of this library.

The balance script uses this module to demonstrate the analysis of an existing SVC configuration. This script demonstrates a scenario where the best set of data migrations can be run in order to rebalance the Virtual Disk Extents and to create an even distribution across the Managed Disk groups. Note that the balance script has not been tested with SVC 4.3.0 and will not work with mirrored vdisks.

The copymanager script demonstrates how to simplify disaster recovery when using the Global Mirror or Metro Mirror remote replication features of SVC. This script can be used to automatically manage FlashCopy point-in-time copies at the disaster recovery site in order to ensure that there is always a consistent data image available. Hence, the remote mirroring relationship can be restarted while retaining this consistent image for use in case the relationship cannot be re-synchronized. The "readme" file for the script gives full details of its use.

Nicholas O""Leary, an SVC test coordinator, has worked on SAN Volume Controller since joining IBM in 2001. This work has mostly been within the test group but did include a year leading a service group helping customers get started with SVC. Mr. O""Leary""s work mainly involves coordinating the testing for various parts of the product but also includes contributing to the group""s test infrastructure and automation strategies.

Andrew Sully, an SVC developer, joined IBM in 2005 on the Industrial Trainee program. His work has mostly involved writing script-based automation for product testing and analysis. Mr. Sully is studying at the University of Warwick in England for a B.Sc. in computer science.