Enterprise Storage Storage Consolidation Using Hitachi Thunder 9520V Workgroup Modular Storage Systems An Application Brief By Steve Smith December 2004
Executive Summary While large enterprises have been using storage area networks (SANs) for years to consolidate and simplify storage, smaller organizations have delayed adopting SANs because of their perceived cost and complexity. But for many, the time for change is now. It s becoming too costly for companies to continue to acquire and administer storage for growing amounts of online data using traditional, directattached storage models. With the Hitachi Thunder 9520V workgroup modular storage systems, Hitachi Data Systems makes consolidated, SAN-based storage affordable and practical for a broad range of organizations. Based on SATA disk technology, the Thunder 9520V system offers high levels of performance and scalability at a low price. The Thunder 9520V system shares the data integrity and availability protections built into all Hitachi enterprise storage systems. Furthermore, Hitachi has worked with its SAN partners to bundle validated, entry-level SAN components at reduced pricing. This paper describes how consolidating storage on a Thunder 9520V system reduces management costs and improves storage utilization. It then discusses how you can use the integrated software capabilities of the Thunder 9520V system to address a wide range of storage requirements, including: : : Snapshot-based backup : : Off-host backup : : Disk-based backup : : Rapid recovery from disk-based point-in-time images : : Tiered, non-rewritable storage for data retention purposes, such as regulatory compliance The Hitachi Thunder 9520V system offers a flexible, scalable platform for addressing both immediate and long-term storage requirements.
Contents Introduction... 1 The Problems with Traditional Storage Models... 1 Consolidating Storage on a SAN... 2 The Hitachi Thunder 9520V Workgroup Modular Storage System as a Consolidation Platform... 4 Simplified SAN Support...5 Availability and Reliability...5 Scalability...5 Manageability...6 Application Optimized Storage Solutions...6 Development and Support Partnerships...7 The Problems with Traditional Backups... 7 Snapshot Backups: Reducing the Backup Window... 8 Application Integration...9 Off-host Backups... 9 Disk-to-disk-to-tape Backups...10 Rapid Recovery for Critical Applications...10 Tiered Storage for Regulatory Requirements...11 Building Your First SAN...12 Summary...13
Storage Consolidation Using Hitachi Thunder 9520V Workgroup Modular Storage Systems An Application Brief By Steve Smith Introduction The amount of data that businesses must manage grows every day and shows no sign of slowing. Companies increasingly rely on business applications for core processes. Government regulations require that certain data be retained and kept easily accessible for years. And online communications are becoming the standard way of doing business in many industries. With the unfolding of these trends, online data is sure to continue its incessant growth. Despite this dramatic increase in data, most businesses haven t fundamentally changed how they manage storage in the last decade. They simply purchase more disk capacity to handle more data. Unfortunately, adding storage generates additional storage management tasks, and administrative resources aren t growing as rapidly as storage requirements. Few companies can afford to double their system administrators on a yearly basis. As a result, many organizations struggle to manage and protect the data they have today, without a strategic plan for the data they ll manage tomorrow. To solve both their immediate and long-term storage crises, companies need to adopt a new storage model: consolidated, storage area network (SAN)-based storage. The Problems with Traditional Storage Models In a traditional, direct-attached storage environment, each server has its own dedicated storage, either internal to the server or directly attached to it. Although this model has made sense for a long time and is initially quite easy to set up, the direct-attach storage architecture doesn t scale well as the amount of data under management grows (see Figure 1). Problems and limitations include: : : Inefficient use of storage. Administrators managing separate pools of storage attached to each server must maintain spare capacity for each server. Distributed across several key applications, the amount of over-provisioned storage can be significant. On the other hand, if an application runs out of storage there is no way to provision from another direct-attached storage system. : : Problems with backup. All of this data must be backed up. Finding the time to perform backups is a challenge, particularly with applications like Microsoft Exchange that are vital and nearly always in use. Sending large backup streams over the local area network can reduce network responsiveness. : : Complexity. System administrators must manage each storage pool separately, often using multiple interfaces and processes if the servers run different operating systems. This makes it more difficult for system administrators to leverage expertise on multiple systems. 1
As a result of these trends, storage consumes an increasing amount of IT resources, both in capital expenditures and management time. Administrators struggle to manage and protect critical data while keeping applications running at peak performance and availability. Consider the problems facing typical small enterprises: : : Critical applications run on multiple platforms. For example, a company might use Microsoft Exchange for e-mail, run Web servers on Linux, and run business applications on Microsoft Windows and UNIX boxes. Managing the storage and capacity planning on different platforms is difficult for the system administrator, who may need to maintain expertise on multiple platforms. : : Storage is distributed among distinct storage islands that must be managed separately. : : To avoid running out of space for any application, the administrator provisions extra storage for each critical server. Figure 1: Traditional, Direct-attached Storage Architecture. Microsoft Windows UNIX Windows Linux UNIX 50% Utilized 50% Utilized 50% Utilized 50% Utilized 50% Utilized Traditional, direct-attached storage creates islands of storage that are difficult to allocate and use efficiently. This storage is difficult and expensive to scale, and the complexity of multiple storage pools and their backup can overtax administrators. Consolidating Storage on a SAN One way to combat the increasing cost and complexity of storage is to consolidate it in a single pool with fewer storage devices shared among multiple servers (see Figure 2). To do this, you need an architecture in which multiple servers can read/write block-level storage from shared physical devices. In short, you need a SAN. By consolidating storage in a SAN you can: : : Reduce the number of physical devices to manage : : Reduce complexity : : Centralize storage management tasks : : Simplify growth and expansion : : Maximize storage utilization and return on investment 2
Large enterprises have widely adopted SANs for this very reason. Smaller enterprises and departmental IT organizations have waited to move to SAN-based storage due to concerns about SAN cost and expertise requirements. But several factors are coming into place to make SANs a viable option for smaller enterprises and departmental units with limited IT resources. : : Maturing SAN technology. The costs of the switches and host bus adapters (HBAs) required to build a SAN have been dropping, while vendors are creating solutions specifically geared to smaller SAN implementations. : : Advances in disk technologies. A new generation of ATA drives is moving into enterprise storage environments, offering significant cost savings over high-performance fibre-attached storage. : : The development of standards and management interfaces. As the industry settles on device management standards, tools are evolving to simplify the management of the SAN environments. With a SAN in place, organizations can consolidate the storage existing on multiple storage devices onto a few larger devices shared among many servers. Figure 2: Consolidated, SAN-based Storage. Microsoft Windows UNIX Windows Linux UNIX Fibre Channel Switch Windows UNIX Windows Linux 85% Utilized 85% Utilized Efficient storage utilization is made possible with consolidated SAN-based storage, which provides shared access to data, centralized management, and nondisruptive scalability. 3
Putting a SAN into place and consolidating data on shared storage systems delivers immediate benefits. : : The spare storage capacity is effectively shared among the various applications, improving overall storage utilization. : : Your administrator can now manage and monitor storage centrally, using a single interface. : : As you need more storage, you can either expand the storage systems or add new storage devices to the SAN. In either case, the addition is nondisruptive. : : Your administrator can now share data between systems much more easily than before. In addition, the shared storage infrastructure offers many options for addressing data protection and data retention requirements. To achieve the benefits of storage consolidation on a SAN, organizations need: : : Tested and validated SAN configurations : : Scalability to address growing storage requirements : : Simplified management of SAN-based storage and SAN components : : Application-specific storage solutions for critical applications Hitachi Data Systems, longtime a leader in enterprise storage systems, has delivered a SATA-based storage system that minimizes storage costs while providing scalable, high-performance storage for consolidation initiatives. The Hitachi Thunder 9520V Workgroup Modular Storage System as a Consolidation Platform The Thunder 9520V system combines enterprise-class performance, functionality, and reliability with affordable SATA disk technology. SATA drives are growing in popularity because of their flexible connectivity and low price. However, they don t traditionally offer the performance or reliability of fibre-attached disk. Organizations consolidating storage for key applications need to be sure of the availability and reliability of the storage platform. The Thunder 9520V system uses SATA drives to keep the total cost of the storage down. However, it doesn t sacrifice performance or capacity; the device can support up to 13TB of storage through expansion modules, and delivers 4.2GB/sec of cached bandwidth. It also offers the same built-in reliability and data protection that customers around the world rely on for their most critical data. In fact, the same software and management interfaces work across the Hitachi Thunder family modular storage and Lightning family enterprise storage lines, allowing you to integrate SATA and fibre-attached disk drive technologies within the IT architecture. 4
Simplified SAN Support To help customers implement their first SANs, Hitachi has worked with partners to package industryleading HBA and SAN switch equipment designed specifically for the initial SAN environment at special, reduced costs. These tested and validated solutions include simplified installation and SAN education CDs to guide you toward getting your first SAN running quickly and effectively. At the same time, any SAN components that have been tested and validated with Thunder family storage systems work with the Thunder 9520V system. Availability and Reliability The Thunder 9520V system comes with all of the built-in data protection that characterizes Hitachi enterprise storage, as well as a few enhancements to improve the overall reliability of the SATA-based storage. Table 1 lists some of the data protection features that help ensure the reliability and availability of essential data. Table 1: Features and Their Data Protection Functions on Thunder 9520V Systems. Hitachi Thunder 9520V Storage System Features Data protection Redundant components Write protection Data corruption protection Error detection Failure analysis Hot global spares Data Protection Functions RAID-5, RAID-1, and RAID1+0 protect data from the failure of any single disk Redundant and hot-swappable components, including hot spares, power supplies, controllers, and communication loop boards All writes are mirrored between controllers Built-in error checking on every read and write Disk error/health checking every half second Hi-Track call-home service/remote maintenance tool identifies errors and orders replacement parts automatically Supports up to 15 hot spare disks and automatically cycles in spares on hard failure or excessive soft failures Scalability The consolidated solution must grow with your storage needs. The Thunder 9520V system supports up to 13TB of storage through expansion modules. You can add more storage to the storage system without disrupting access to existing data. The Thunder 9520V system also offers room to grow in terms of connectivity. It offers 512 LUNs and virtual storage ports that optimize your connectivity while reducing your infrastructure complexity. It supports a wide range of server operating systems, from commercial Windows, UNIX, and Linux implementations to Novell NetWare and HP OpenVMS. 5
Manageability The Thunder 9520V system comes with built-in management capabilities in the Hitachi Resource Manager utility package. The Hitachi Storage Area Management (SAM) Suite of software works across all Hitachi Thunder family and Lightning family storage devices as well as other vendors storage systems, offering consolidated and centralized storage management. In addition, as shown in Table 2, the Thunder 9520V system offers other software capabilities that are available with Hitachi enterprise storage. Table 2: Supported Software Modules and Their Functions on Thunder 9520V Systems. Hitachi Thunder 9520V Storage System Supported Software Hitachi ShadowImage In-System Replication Hitachi Copy-on-Write Snapshot (formerly QuickShadow) Hitachi Cross-System Copy (formerly RapidXchange) Hitachi Data Retention Utility (formerly Open LDEV Guard) Function Uses a mirrored data image to create a clone of key data for backup, rapidrecovery, or off-host processing Creates a logical, point-in-time replica of data for rapid recovery purposes, requiring less storage than a full data clone Replicates data easily between Hitachi storage systems Creates write once, read many (WORM) storage on Hitachi storage systems for regulatory compliance and data retention requirements Application Optimized Storage Solutions Hitachi Data Systems works with major application vendors to create integrated, optimized storage solutions that address specific application challenges. For example: : : Hitachi Data Systems and Microsoft have a long-standing partnership to provide tightly integrated, fully tested, and jointly supported solutions leveraging Hitachi storage and Microsoft servers and applications. The companies have created recommended storage configurations, best practices, product certifications, and product integration. Hitachi ShadowImage In-System Replication software is fully integrated with Microsoft s Virtual Shadow Copy Service (VSS) application-aware data replication capabilities. : : Hitachi, Ltd., Hitachi Data Systems, and Oracle maintain a strategic alliance that includes joint technology, services and support, and sales and marketing efforts. Hitachi provides innovative solutions that embed knowledge about the application in the storage environment, leveraging collaborative development efforts with Oracle. Through these partnerships and integrated Hitachi offerings like ShadowImage software, Hitachi Data Systems offers customers storage solutions that are optimized for the application environment. Examples include: : : Snapshot-based backups for Microsoft SQL Server or Oracle databases : : Off-host backups for Exchange databases : : Rapid recovery for Active Directory or Exchange databases 6
Development and Support Partnerships Hitachi, Ltd., and Hitachi Data Systems maintain close relationships with key industry leaders so that customers can be assured of interoperable solutions. : : SAN solution providers. Hitachi Data Systems tests and validates SAN solutions from leading providers such as Brocade, McDATA, and Emulex, and bundles integrated solutions at competitive prices. : : Microsoft. Hitachi Data Systems and Microsoft have a long-standing partnership to provide tightly integrated, fully tested solutions that leverage Hitachi storage and Microsoft servers and applications. The companies have created recommended storage configurations, best practices, product certifications, and product integration. With a consolidated, SAN-based storage architecture, you have the ability to address many of today s storage challenges. Let s start by looking at that most common and necessary function, backup. The Problems with Traditional Backups In a traditional, network-based backup scenario, a backup server retrieves data from multiple servers over the local area network (LAN), and (as shown in Figure 3) then sends that data to a tape drive or tape library. Figure 3: Traditional LAN-based Backup Sends Large Amounts of Data over the LAN. Backup Data Path Tape Backup Server Storage Storage Storage Storage Network traffic suffers delays, and its performance can be degraded by traditional LAN-based backup, which competes with business activity for network transmission time. As the amount of data to back up grows, the amount of network traffic generated increases. Delays in network traffic prolong the backup. Even online backups usually degrade performance on running applications, so the length of the backup window is a significant concern. These backups most frequently occur at night, during the hours of least system usage (although Webbased operations pretty much eliminate the concept of off-hours or downtime). As a result, the system administrator must monitor and troubleshoot any backup problems in the morning. A backup that failed may not be retried until the following night, leaving more data at risk and prolonging recovery times if a problem occurs. 7
Using the Thunder 9520V system in a SAN environment offers several options for improving backup performance and recoverability. Snapshot Backups: Reducing the Backup Window The ShadowImage In-System Replication software provides an alternate image or data clone for performing backups, significantly reducing the impact of a backup on a critical application. With less backup impact, administrators can take more frequent backups. Using ShadowImage software, administrators can create a point-in-time copy of critical data and then perform the backup from that cloned volume instead of the production data (see Figure 4). : : For cold backups (backups in which the application is shut down), the amount of time required to perform the copy is minimal. : : For online backups, any impact of the backup is fleeting as the data clone is created in seconds. The backup software would then access the clone volume instead of the production data volume. Hitachi Data Systems has worked with multiple backup software vendors to build seamless integration for snapshots into their software. Figure 4: A Snapshot Backup Uses a Point-in-time Copy as the Backup Source. Local Area Network Application Server Backup Server Tape Fibre Channel Switch Application Data Point-in-time Cloned Volume Backup Data Path To significantly reduce the impact of a backup on a critical application, administrators can use ShadowImage software create a point-in-time cloned volume of critical data and then perform the backup from that cloned image instead of the production data. 8
Application Integration ShadowImage software offers integration with Microsoft s VSS snapshots. VSS coordinates between the application requesting a data copy and the data copy software provider (ShadowImage software on the Thunder 9520V system). The application manages the process of preparing the data for a consistent point-in-time copy, potentially quiescing the database, while the software provider creates the data copy. VSS data copies are currently supported on Microsoft Windows Server 2003, Microsoft SQL Server 2000 and above, and Microsoft Exchange Server 2003. For earlier Microsoft servers and other applications, you must directly perform the steps required to coordinate the data copy with the application. These processes can be automated in scripts. Off-host Backups Taking data clone backups one step further, in an off-host backup another server can mount the clone volume and perform the backup independently of the production system (see Figure 5). If the system that mounts the data clone is a backup server, then the data doesn t travel over the LAN at all, so the backup takes place at direct-attached speeds. Figure 5: In an Off-host Backup, the Backup Data Travels Only over the SAN. Application Server Backup Server Tape Fibre Channel Switch Application Data Point-in-time Cloned Volume Backup Data Path By using another server to mount the clone volume, backup can be performed independently of the production system. This configuration has many advantages, including: : : Minimal impact on production application or the application server : : Minimal LAN traffic; the data itself travels over the SAN to the backup server and the tape drive. 9
Disk-to-disk-to-tape Backups Many organizations use disk-based backups to speed backup and recovery times. Most networked backup software supports disk as well as tape for backup storage. Disk-based backups can be performed from clone or snapshot images for rapid, low-impact backup operations. Because of its low cost and high performance, the Thunder 9520V system makes a good repository for disk-based backups. Note that for data retention, archiving, and disaster recovery purposes it s generally necessary to copy disk-based backups to tape eventually. Rapid Recovery for Critical Applications This paper has looked at ways to alleviate the backup time; recovery time is another concern. Backing up to disk is one method for speeding recovery; rather than loading data from tape, you load it directly from disk. Another rapid recovery approach is to maintain multiple point-in-time images as disk-based Hitachi Copy-on-Write Snapshots (formerly QuickShadow snapshots), with the ability to retrieve those images at any time if the production data has become corrupt or invalid through software or user errors. If you re running a transaction-based system like Microsoft Exchange, Microsoft SQL Server, or an Oracle database, you can restore a snapshot image as of a specific point in time, then play through the transaction log to reach the point before the data corruption occurred. The more recent your backup image, the fewer transaction logs you must replay and the faster the recovery. For critical applications, you may want to perform frequent snapshots to support very quick recovery. Each ShadowImage data clone is the same size as the production volume it is copying. The Copy-on- Write Snapshot software maintains logical snapshots by tracking changed blocks in the snapshot volume. Functionally, they work like a ShadowImage clone, but they require only a fraction of the storage of the source volume. (The actual size of the Copy-on-Write Snapshot depends on the amount of changes made to the original data.) Using Copy-on-Write Snapshot software, an administrator can keep multiple recent images of critical applications (see Figure 6). For example, they could create point-in-time images of Exchange data at 8 a.m., 11 a.m., 3 p.m., and 6 p.m. If an error occurs at 12 noon, corrupting the database in one storage group, the administrator could reload the 11 a.m. snapshot and then run transactions until the error at 12 noon. E-mail service would be restored very quickly. 10
Figure 6: Maintaining Multiple Copy-on-Write Snapshots for Rapid Recovery. Application Server Fibre Channel Switch Application Data Hitachi Thunder 9520V Storage System 8 am today 11 am today 3 pm yesterday 6 pm yesterday Using Copy-on-Write Snapshot software, an administrator can keep multiple recent images of critical applications. The more recent the backup image, the fewer transaction logs that must be replayed and the faster the recovery. : : Because they are logical images only, Copy-on-Write Snapshot images require access to the production data volume. They cannot be split and loaded on another machine. : : Snapshots do not provide complete data protection or disaster recoverability. They protect data from logical errors such as software and user errors, but not from data loss due to hardware problems or catastrophic server/storage failures. Tiered Storage for Regulatory Requirements The Thunder 9520V system fits into tiered data/data retention strategies as well. For example, a company s auditors may want to store financial data on non-rewritable media, and to have rapid access to that data for three years. The SATA-based storage in the Thunder 9520V system and the Hitachi Data Retention Utility software (formerly Open LDEV Guard) provide a cost-effective platform for secure disk-based data retention (see Figure 7). Hitachi Cross-System Copy software (formerly HiCopy) moves data quickly and easily between multiple tiers of Hitachi storage systems. This enables a Thunder 9520V system to serve as a cost-effective, longterm, data retention repository for other applications using Hitachi storage systems. 11
Figure 7: Maintaining Archival Data on Non-rewritable Storage. Microsoft Windows UNIX Windows Linux UNIX Fibre Channel Switch Other storage Production Data Production Data Production Data Archival Data Hitachi Thunder 9520V Storage System with Hitachi Data Retention Utility software (formerly Open LDEV Guard) Production Data The Thunder 9520V system supports tiered data/data retention strategies, and with Data Retention Utility software it provides a cost-effective platform for secure, disk-based data retention. Data Retention Utility software turns disk-based storage into write once, read many (WORM) storage, so that auditors can be sure the data has not been changed or tampered with during its retention period. Yet the disk-based storage also provides rapid access to audit or other reporting requests. Building Your First SAN Consolidating and sharing storage between servers requires a storage area network or SAN. Although many organizations have delayed implementing SANs due to their perceived cost and complexity, SAN technology has evolved, matured, and dropped in price in recent years. To ease the building your first SAN, Hitachi Data Systems offers pre-tested SAN Starter Kits with industry-leading partners Brocade, Emulex, and McDATA, integrating entry-level yet scalable SAN configurations. Brocade and McDATA provide switches while Emulex provides the HBAs. These Starter Kits reduce your upfront SAN investment as well as ongoing support costs. In addition, Hitachi Data Systems and its Channel partners offer a number of services to help you build your first SAN (or add more components to an existing SAN). These services range from assessing your needs to designing and implementing the SAN infrastructure. Once the SAN is in place, it s easy to add servers and/or storage without disrupting your production applications. For example, you can add a SATA-based Thunder 9520V system to archive data that you need to secure and protect for compliance purposes. And, the Thunder 9500 V Series storage systems support a wide variety of operating systems, so you can connect, consolidate, and centralize management of storage for a broad range of business applications. 12
Summary Consolidating storage on the Thunder 9520V system offers relief from the problems of managing growing amounts of distributed storage. The immediate benefits in better storage provisioning and simplified management can bring a rapid return on investment for the initial SAN implementation. But consolidated, SAN-based storage is more than a one-time solution. The Thunder 9500 V Series modular storage systems are strategic platforms for addressing long-term storage requirements: : : The SAN infrastructure lets you share information across disparate platforms, improving access to valuable business information. : : Hitachi Thunder family systems offer scalable storage that can grow with you for years to come. And if you should choose to expand to higher-end, fibre and SATA intermixed storage in a Thunder family system, you can use the same software across all Hitachi storage systems. : : Because it supports so many platforms, Thunder family storage keeps your platform options open as you balance UNIX, Linux, Windows, and possibly other operating systems in the IT infrastructure. The Hitachi SAM Suite of software helps you manage heterogeneous storage as well, so you can leverage existing storage assets. 13
Hitachi Data Systems Corporation Corporate Headquarters 750 Central Expressway Santa Clara, California 95050-2627 U.S.A. Phone: 1 408 970 1000 www.hds.com info@hds.com Asia Pacific and Americas 750 Central Expressway Santa Clara, California 95050-2627 U.S.A. Phone: 1 408 970 1000 info@hds.com Europe Headquarters Sefton Park Stoke Poges Buckinghamshire SL2 4HD United Kingdom Phone: + 44 (0)1753 618000 info.eu@hds.com Hitachi Data Systems is registered with the U.S. Patent and Trademark Office as a trademark and service mark of Hitachi, Ltd. The Hitachi Data Systems logotype is a trademark and service mark of Hitachi, Ltd. Hi-Track is a registered trademark and Thunder 9520V, ShadowImage, Resource Manager, and Application Optimized Storage are trademarks of Hitachi Data Systems Corporation. All other product and company names are, or may be, trademarks or service marks of their respective owners. Notice: This document is for informational purposes only, and does not set forth any warranty, express or implied, concerning any equipment or service offered or to be offered by Hitachi Data Systems. This document describes some capabilities that are conditioned on a maintenance contract with Hitachi Data Systems being in effect, and that may be configuration dependent, and features that may not be currently available. Contact your local Hitachi Data Systems sales office for information on feature and product availability. Hitachi Data Systems sells and licenses its products subject to certain terms and conditions, including limited warranties. To see a copy of these terms and conditions prior to purchase or license, please go to http://www.hds.com/products_services/support/warranty.html or call your local sales representative to obtain a printed copy. If you purchase or license the product, you are deemed to have accepted these terms and conditions. 2004, Hitachi Data Systems Corporation. All Rights Reserved. WHP-172-00 December 2004