Global Headquarters: 5 Speen Street Framingham, MA USA P F

Transcription

1 Global Headquarters: 5 Speen Street Framingham, MA USA P F WHITE PAPER What Issues Does Storage Virtualization Solve? The Benefits of Hitachi's Virtualization Solutions Sponsored by: Hitachi Ltd. Yasusuke Suzuki March 2006 Masaaki Moriyama EXECUTIVE SUMMARY Virtualization is a technology designed to streamline the management of complex storage systems by freeing IT resources from their physical environment and constraints, converting them into logical resource units. In recent years, rising administrative costs due to such influences as rapidly growing volumes of data and worries over security risks have become a major issue. Consequently, demand for virtualized storage as a means to resolve rising costs is growing. Storage hardware and software vendors, especially in the United States, offer a variety of virtualization solutions. Although recognition of storage virtualization is lower in Japan than in Europe and North America, Japanese companies are beginning to understand the features and benefits of storage virtualization and are planning to introduce solutions suited to their business needs in order to improve their IT competitiveness. This white paper summarizes the benefits of and technical trends in storage virtualization and delineates the potential value of Hitachi's virtualized storage to its customers. Storage Virtualization Despite the benefits promised by virtualization technologies, companies can still find it difficult to recognize their value, given virtualization's main focus of simplifying management as opposed to cultivating new customers or shortening lead times. Rather, virtualization improves a company's competitiveness indirectly, such as by reducing fixed expenses or IT risk. Storage vendors and some users, however, are showing a high level of interest in this technology as a key to alleviating the complexity of infrastructure management. Below we describe storage virtualization technology and its benefits.

2 What Is Storage Virtualization? Virtualization is a technology used to help companies administer storage, as well as servers, networks, and the like, in order to reduce the administrative burden caused by the increasing scale and complexity of IT infrastructure. It frees IT resources from their physical connections, making them available to users (or applications) as logical resource units. An analogy would be an agreement for home electricity usage: If usage is defined in terms of amperes, then the user does not need to worry about whether the electricity comes from thermal or nuclear power. IDC's definition of storage virtualization includes the following functions:! The availability of logical volumes separate from such physical constraints as hard-disk capacities! The ability to group resources in a multivendor storage environment and reallocate them independently of block size or physical location! Automated storage optimization and policy-based automated storage management Even if the definition were clarified in this way, however, many users would probably still have difficulty understanding the difference between a storage area network (SAN) and virtualization without a side-by-side comparison. The goals of SAN and virtualization technologies are similar in that each looks to simplify management and improve scalability. A SAN uses a network to separate the connection between servers and storage from physical limitations, while storage virtualization creates a logical separation via software (including controller microcode). To put it another way, SAN integrates storage networks while virtualization integrates storage management. When adding storage, if one connects the storage to the network via a SAN, the added storage does not have to be physically near the server that uses it. But since the connection to the added storage is initiated from a single server, the link between the storage volume and the server (or application) remains. In the case of virtualized storage, servers only use storage volumes logically, so their location naturally bears no relation to the physical storage units. Added storage only increases the pooled total storage capacity, so there is no need for management to be aware of their individual connections. Trends in Storage Virtualization As the need for storage virtualization increases, vendors are bringing to market new virtualized storage products. A number of virtualization methods exist and are briefly outlined below:! Server-based virtualization: This method places a management program on the host. This has the benefit of leveraging conventional SAN-side assets as is. 2 #J IDC

3 ! Fabric-based virtualization: This can be done via network switches or appliance servers, but in either case, independent appliances (switches, routers, dedicated servers) placed between servers and storage have a storage virtualization function. The purpose is to reduce the impact on the use of the existing SAN and servers.! Storage array based virtualization: This is virtualization implemented at the storage-system level. The virtualization method offered by Hitachi falls into this category. Each vendor selectively offers solutions combining these virtualization methods in accordance with its product portfolio and customer base. Issues Resolved by Storage Virtualization There are three main benefits of introducing storage virtualization:! Manageability increases the management capacity per administrator by streamlining management. It also reduces management work hours and facilitates the acquisition of management skills.! Scalability makes it easier to respond to requirements for added capacity and the like. It also enables a fast response to system performance requirements following rapid changes in demand.! Availability reduces downtime due to failures or configuration changes. These points are similar to the benefits generally touted for IT infrastructure integration. For example, the above benefits may also be listed for the introduction of a SAN, which is storage network integration. Virtualized storage operates on a more abstract level than SANs; in other words, hardware limitations have little effect on it. This could be said to improve convenience, but what does it mean for the user? The customer issues listed in Table 1 are responses to a corporate user survey conducted by IDC regarding storage issues. We rated the appropriateness of storage environments using direct-attached storage (DAS), SAN (no virtualization), and virtualized SAN as solutions to these issues. The right column shows the reasons for differences in appropriateness. Since the connection environment has a large impact on the effectiveness of the solution for streamlining backups and disaster recovery, there is a large gap between DAS and SAN, but virtualization is not necessarily required. But issues relating to ease of management (e.g., dealing with data growth, lack of administrators/reducing operating costs, and effectively using resources) are where the benefits of virtualized SAN over simple SAN come to the fore. Although there are cases for performance concerns when migrating from a DAS to a SAN environment, most can be resolved by leveraging the flexibility gained through virtualization to dynamically hot-allocate caches, ports, and other resources to high-load applications IDC #J

4 TABLE 1 Appropriateness of Technologies for Storage Issues Customer Issue DAS SAN Virtualized SAN Factors Streamline backup Low High High Ease of backup integration Deal with data growth Low Medium High Ease of provisioning/expansion Disaster recovery Low High High Remove backup development environment Lack of administrators Reduce operating costs Low Medium High Flexibility of architecture, ease of management Difference in personnel costs/storage utilization Effectively use resources Low Medium High On-demand resource reallocation Performance High Medium High Performance tuning Source: IDC, 2006 Hitachi's Storage Virtualization Solutions In September 2004, Hitachi released its TagmaStore Universal Storage Platform (TagmaStore USP), an enterprise virtualization array with built-in virtualization functionality. Then, in July 2005, it released its TagmaStore Network Storage Controller NSC55 (TagmaStore NSC), a virtualization controller/array with TagmaStore USP's virtualization functionality for the midrange class. Hitachi's virtualization products are competitive in terms of storage-pool scale, flexibility of architecture, and ability to achieve centralized management of multivendor products. These capabilities, combined with the software functionality of the HiCommand Suite storage management software, have Hitachi well positioned to support its Application Optimized Storage (AOS) solutions. Below we explore the potential value that Hitachi's virtualized storage provides to businesses. 4 #J IDC

5 Features of Hitachi's Virtualized Storage Although TagmaStore USP/TagmaStore NSC has several features worthy of attention, we examine two of them in this white paper: Universal Volume Manager and Virtual Partition Manager. Universal Volume Manager is a feature that centrally manages the built-in storage of TagmaStore USP/TagmaStore NSC, as well as multiple heterogeneous external storage solutions connected to them. The term "centralized management" includes volume management, capacity management, access security management, and path management. Support for external storage includes older Lightning/Thunder models, Hitachi's midrange products and nearline products, as well as other companies' disk storage. Adding in the capacity that can be managed via external storage, these solutions have impressive scalability: TagmaStore USP up to 32PB, and TagmaStore NSC up to 16PB. It is also possible to effectively use existing assets by converting them to disk-to-disk (D2D) backup as secondary storage. The second feature highlighted, Virtual Partition Manager, partitions TagmaStore USP/ TagmaStore NSC resources by application or business process. This feature makes it possible to transparently port storage that had been operated by multiple departments to a structure that manages it by business process. The Virtual Partition Manager makes it possible to prevent interference between partitions and to maintain a high level of confidentiality for each. In addition to disk capacity, the manager feature can control the allocation of cache memory and server connection ports, enabling the management of quality of service (QoS) for each business process independently. When allocating cache capacity, the storage management software, HiCommand Tuning Manager, can be used as a tool for determining whether the allocated size is optimum, enabling stable operation of the storage system via proactive monitoring. Introducing Hitachi's Virtualized Storage Until now, we have explored only the potential benefits of storage virtualization. Although users may understand the benefits, they may think that virtualization technologies aren't feasible for their company for various reasons. Or they may delay adoption until much later, for fear of adversely impacting their current environment. These views, however, may be incorrect and due to lack of understanding. Figure 1 illustrates a sample introduction of Hitachi's virtualized storage. Numbers 1 to 4 in the figure are the stages of change. One example of user misunderstanding is thinking that the introduction of virtualized storage proceeds from stage 1 on the upper left, a mixed SAN and DAS environment, straight to stage 4 on the lower left, virtualization. That kind of one-step migration is not necessary. In fact, it is possible to introduce virtualized storage in stages, leveraging the scalability that virtualized storage provides IDC #J

6 Using the previously mentioned Virtual Partition Manager, it is possible to migrate to a virtual storage environment with the same utilization conditions as the existing DAS environment. For example, consider the migration of individual back-office systems to an integrated environment in a conventional storage integration initiative:! Responsibility for managing the related storage in a SAN environment was usually given to the information systems (IS) department instead of allowing departments to boost server configurations on an ad hoc basis (in a departmentmanaged DAS environment).! It was thought that the IS department was more capable of responding to sudden demands when performance degraded due to increased data.! Virtual Partition Manager, however, eliminates demand response concerns because it allocates cache memory to each server and then increases each allocation as necessary. Each business division can continue operating the same way as before integration. Moreover, capacity in a staged integration is highly scalable: TagmaStore USP itself can scale up to 332TB (with 300GB HDD installed), and TagmaStore NSC can scale up to 69TB. For this reason, the system is not susceptible to impact, even if the scope of integration grows to an extreme degree from initial plans. It is also possible to effectively use existing assets as external second-tier disk storage. In other words, it is possible to make a "small start," introducing TagmaStore USP/TagmaStore NSC for a portion of storage and then expanding in stages as necessary. Even if the timing of the updating of the existing storage system is spread out, it is possible to seamlessly integrate systems as their shelf lives expire. Naturally, in some cases, the decision will be made to not integrate a DAS architecture for reasons of performance. In other words, virtualized storage and DAS could be used side by side as in stage 3 (lower right) in Figure 1. This could happen as a real-life result of choosing database and other performance over management load. When introducing virtualized storage, it is fine to virtualize the portions that are needed, as it becomes necessary. In stages 2 to 4 in Figure 1, AOS management in a multitier storage environment is accomplished by using HiCommand Tiered Storage Manager. This makes it possible to migrate data to the optimum storage in accordance with the properties of the data (e.g., value of use and access frequency) without stopping business. Additionally, policy-based automation is provided through collaboration with JP1 integrated system management. Automated data migration plays a vital role in the management of fixedcontent data, predicted to have a high rate of growth within the industry. In addition to being on the leading edge of virtualization technology, TagmaStore USP/TagmaStore NSC is a platform that offers customers a wide range of value in collaboration with the rich software offerings of the HiCommand Suite. 6 #J IDC

7 FIGURE 1 The Virtualized Storage Introduction Process SAN DAS TagmaStore USP SAN DAS Tape Library 1 External Storage 2 DAS TagmaStore USP SANRISE USP 4 TagmaStore USP 3 External Storage External Storage Note: The stages are the same whether TagmaStore USP or TagmaStore NSC is used. Source: IDC, 2006 Hitachi's Business Opportunities and Challenges with Virtualization Solutions Currently, technology is progressing from DAS to network storage, but the following user situations will also encourage storage integration:! Increasing information security risk. There are many more difficulties ensuring security in a distributed environment than with centralized management on a mainframe because it is a great burden for each department to implement a high level of security management. An increasing number of businesses are sacrificing the efficiency of distributed processing for centralized management due to the increasingly severe impact of security incidents IDC #J

8 ! Establishment of IT governance. There is a demand for IT governance due to the trend toward focus on corporate social responsibility (CSR) and the need to maintain compliance. It is sometimes deemed necessary to integrate applications and business systems in order to practice governance and build IT control systems, and the integration of storage also expands to the enterprise level.! Need for streamlined management due to growth of retained data. The amount of data companies store is skyrocketing. The growth of unformatted data is especially fast, being a prototypical example. Businesses, however, cannot increase their numbers of administrators in proportion to the amount of data. This creates a need to change to an architecture that makes it possible to increase the amount of data managed per operations technician. As factors such as these prompt changes to the storage environment, there are a growing number of situations where building a SAN alone is not sufficient in terms of efficiency and system flexibility, and a virtualized solution is needed. Consequently, the opportunities for Hitachi's virtualized storage business are likely to grow. Currently, however, not all of the companies with these issues understand the benefits of virtualization technology, nor are they considering its introduction. IDC sees the following issues for Hitachi as a solutions vendor:! Most users do not sufficiently understand the features of virtualization technology, such as the ability to migrate to virtualized storage while enabling each department to continue using its storage in the same way. The mission of Hitachi as a leading vendor is to raise awareness of the concrete value of virtualized storage.! Since every company in Japan will not have a storage expert, the use of virtualized storage must be proposed. It is important to deeply understand the business needs of each company and propose a virtualized storage solution with a high return on investment (ROI). Copyright Notice External Publication of IDC Information and Data Any IDC information that is to be used in advertising, press releases, or promotional materials requires prior written approval from the appropriate IDC Vice President or Country Manager. A draft of the proposed document should accompany any such request. IDC reserves the right to deny approval of external usage for any reason. Copyright 2006 IDC. Reproduction without written permission is completely forbidden. 8 #J IDC