Techworld asked Symantec a number of questions about its storage virtualisation ideas and Sean Derrington, Senior Group Manager, Storage & Server Management Group, at Symantec Corporation provided the answers below.

Can Veritas continue to prosper if it does not offer a storage array virtualisation product?

Absolutely. Symantec offers a wide range of security, availability, and storage management software solutions for customers. Moreover, our customers vary from individuals all the way up to Fortune 50 companies. Symantec’s storage management solutions enable IT Organizations to manage storage in a heterogeneous environment (both storage hardware and server operating systems) in a consistent manner while reducing costs.

If Veritas is going to work with other vendor's storage array virtualisation products will it have to write an interface per product or is a standard emerging for this?

Symantec currently works with nearly every storage hardware vendor today. As traditional storage subsystems can be considered “storage array virtualization” we don’t have to write a unique interface. However, if you’re speaking about network based virtualization (e.g., EMC Invista, IBM’s SVC) then the answer is possibly.

Network-based virtualization appliances introduce another layer of complexity (installation, ongoing management, upgrades) and prohibit applications from “seeing” storage LUNs. While some of Symantec’s solutions (Storage Foundation, Dynamic Multi-pathing, etc.) will work with EMC Invista (as an example) without unique interfaces, other software is still being tested as Invista is not generally available.

Symantec believes storage virtualization is a critical technology, but it will not be a panacea and must be considered as an integral component in a broader server and storage infrastructure and operational paradigm shift (including people, process, and technology).
Furthermore, we continue to analyze and develop storage virtualization capabilities with a SAN-wide view, that is we do not constrain hosts, network, or storage subsystems and each “layer” can be optimized. Furthermore, we believe the virtualization intelligence should not be constrained by, and consequently require IT Organizations to deploy proprietary intelligent FC directors (e.g., Cisco MDS).

We’re developing centralized management capabilities that will afford IT Organizations the ability to accomplish many business critical tasks such as:

- Implement a SAN-wide virtualization strategy that is non disruptive to the existing storage infrastructure
- Improve data protection capabilities that enable tighter integration with backup/recovery software for disk-based recovery
- Create a point-in-time copy (full volume or space optimized) of an application(s) from a pool of storage which is not constrained by physical storage subsystem enclosures (e.g., multi-vendor and multi-tier capabilities)
- Enable servers to have a SAN-wide view of a heterogeneous storage pool, and further promote a LUN as available and visible to more than a single host while simplify and consolidating tasks by using a SAN-Wide tool set
- Improve application availability and performance by integrating with application clustering and priority-based application workload management
- Support a server consolidation, blade server, and server virtualization strategy
- Remove the mind set of physical storage enclosures and truly provide application services with a SAN-wide view of a storage pool
- Improve the effectiveness and efficiency of provisioning storage SAN-Wide

Symantec believes a SAN-wide storage virtualization approach provides the most agile infrastructure enabling an IT Organization to optimize its hardware resources. IT Organizations are free to select the most appropriate operating system, server architecture, FC director, storage subsystem, etc. without compromising functional capabilities or being reduced to a lowest common denominator compatibility matrix (as is the case with many network-based virtualization offerings). Moreover, with a SAN-wide approach, the solution of storage virtualization isn’t limited to a subset of applications within the IT portfolio, but rather is an all encompassing storage infrastructure and operational discipline that becomes “standard operating procedure” for information management. Additionally, storage services can be integrated with, and aware of, application services. Specifically, application resources can be relocated both intra and inter-server hardware resources after an event (e.g., sub par application performance, server hardware failure, etc.) based upon priority application workload management.

Furthermore, as storage services are application and database aware in a SAN-wide approach, additional capabilities can include:

- Information (structured, semi-structured, or unstructured) can be dynamically moved from one virtualized LUN to another based upon the changing value of the information, benefiting from tiered storage and information lifecycle management
- Information can be protected via replication capabilities supporting the most stringent recovery point objectives and are not constrained by distance limitations
- Storage copy services can be integrated with application failover services providing increased availability services to the business
- Information mobility and migration is dramatically increased, and although the current SF capabilities are market leading, providing SF SAN-wide visibility will dramatically improve storage agility
- Application performance can be optimized within a server, throughout the SAN I/O path, and down to the physical disk drive
- Centralized management capabilities (i.e., reporting, SAN management, storage resource management, storage utilization, storage provisioning, etc) are not compromised since a SAN-wide visibility into the entire server and storage infrastructure is maintained

Does Veritas have a view about the best location for storage array virtualisation? Should it be in the fabric, in a clever drive array controller or elsewhere?

In addition to the comments made in the prior questions, virtualization intelligence resides, and should reside at the server, network, and storage controller layer. Yes there are some virtualization functions that can reside at the network layer, and Symantec does believe that networks will continue to gain intelligence over the long-term, as vendors work to create an industry standard set of network-based interfaces (e.g., Fabric Application Interface Specification--FAIS). When those standards are mature, we plan to integrate our solutions with the standard external APIs just as we do today with array based technology (e.g., VERITAS Cluster Server integration with EMC SRDF). However, while the vision for VERITAS Storage Foundation for Networks was development of software for a standard network platform, the reality is that we were developing custom firmware for embedded devices, and that is not our business. We do not want customers to be locked into a hardware agenda. Moreover, we felt that the vision of centralized management and SAN-wide virtualization could be achieved more effectively by our server software stack - Storage Foundations, CommandCentral-Storage and the new 5.0 technologies.

Symantec continues to heavily invest in expanding Storage Foundation -- our current, market-leading, host-based storage virtualization technology. Storage Foundation 5.0, and future versions, will introduce SAN-wide virtualization, enhanced tiered data sharing, and centralized server and storage management. These features will focus on optimizing host-based functionality while significantly increasing manageability across the customer’s IT infrastructure. IT Organizations will be able to leverage Symantec's solutions to solve common problems in their SAN such as storage pooling and provisioning, data migration, and online data protection. This approach will give customers a seamless and painless upgrade path, and allow them to improve their environments today while adopting advanced functionality on-demand on an as-needed basis.

What Veritas software will run on the Cisco MDS9000 products?

Symantec has invested in the emerging area of SAN-based network intelligence over the past 4 years with VERITAS Storage Foundation for Networks (VSFN). Earlier this year we decided to reduce our investment in this area for several reasons:

- Network-based intelligence is an emerging technology and Symantec believes it will be some time before both the technology and standards are mature for wide-spread adoption. Consequently, Symantec is focusing its R&D developments on other SAN-Wide storage virtualization technologies that are both mature, ready for wide-spread adoption, and standards based.

- IT Organizations wish to solve immediate storage management requirements today; rather than focus on network-based intelligence. Symantec believes it can help solve these storage management requirements more efficiently by capitalizing on today’s more proven technologies.

- While large IT Organizations have resources to perform extensive testing of emerging products (as they’ve done with VSFN), the vast majority of IT Organizations prefer that Symantec focus on delivering better storage management with today’s technologies, increasing the depth of integration with other products (e.g., CommandCentral Storage), and improving interoperability and automation between host and SAN management solutions.

- Furthermore, network-based virtualization products do not deliver value to IT Organizations in such areas as,
- Remote data replication, either synchronous or asynchronous over any distance
- Tiered storage, placing information on the appropriately priced storage hardware based upon the changing value of the information
- Application and database performance tuning, map performance implications from the server to physical disk drives
- Support for server virtualization and server consolidation, and
- Support existing controller-based functional storage software (e.g., EMC TimeFinder, IBM PPRC), which is not supported when used in conjunction with network-based storage virtualization.