Taking Modular Storage to New Heights

Transcription

1 Enterprise Storage Taking Modular Storage to New Heights Hitachi TagmaStore Network Storage Controller Model NSC55 A White Paper By Hu Yoshida January 2006

2 Executive Summary The Hitachi TagmaStore Network Storage Controller model NSC55 is a new storage controller in the TagmaStore family. The NSC55, powered by the Hitachi Universal Star Network crossbar switch architecture, delivers the innovative controller-based virtualization, logical partitioning, and universal replication capabilities introduced with the category-creating Hitachi TagmaStore Universal Storage Platform for open systems and mainframe environments. While previous products in this line Universal Storage Platform models USP100, USP600, and USP1100 are a seamlessly upgradable family of intelligent storage control units for the enterprise data center, the NSC55 is designed for the requirements of entry-level enterprises and fastgrowing midsize organizations, distributed enterprises, and non data center environments. The NSC55 addresses the growing need for highly available, high-function, highcapacity storage, in a packaging and price point to meet the unique requirements of smaller enterprises. Traditional modular storage systems, with their basic dualcontroller architecture, can no longer provide these organizations with the resilience, speed, and scalability necessary to satisfy today s business requirements. The NSC55 is a modular, 19-inch rackmounted version of the TagmaStore Universal Storage Platform, with significantly reduced footprint, power, cooling, and price. It provides the first modular storage system not limited to the traditional dual-controller architecture. With 32 processors for nonstop availability, a switched global cache for scalable performance, enterprise-class data-mobility functionality, and virtualization that provides connectivity to thousands of host processors and simplified management of up to 16PB of internal and external storage, the NSC55 takes modular storage to new heights, eliminating the limitations of a dual-controller design. With new advanced packaging and environmentals, the NSC55 brings the high-end functionality and manageability of the Universal Storage Platform within reach of smaller or distributed enterprises and organizations.

3 While some may consider the NSC55 to be an enterprise-class storage controller due to its functionality and availability, the modular classification of the NSC55 is based on packaging and pricing for the non data center environment. The lower price also reflects the warranty and maintenance levels of modular storage. Tax authorities might specify a different depreciation schedule for modular storage, which may affect lease or buy decisions. While an NSC55 may be located in a data center, a USP100, USP600, or USP1100 cannot be located outside of a data center environment. An NSC55 is not designed to scale beyond 32 processors in the controller and 240 disk drives. If virtually unlimited scalability is required, one should choose the USP100 over the NSC55.

4 Contents Business Requirements for a New Modular Storage Architecture... 1 Limitations of Traditional Dual-controller Modular Storage...2 Network Storage Controller Model NSC55: a New Modular Storage Architecture... 3 Increased Connectivity and Safe Multitenancy...3 Write Mirrored Global Cache for High Availability...4 Packaged for the Modular Environment of the Midsized Organization...4 Private Virtual Storage Machines for Quality of Service...4 Enterprise Data Mobility...4 The Value of Virtualization...4 Highly Available Capacity When and Where You Need It...4 A Comprehensive Suite of Storage Management Software...4 A Clean Green Machine...4 Designed for Midsized Organizations... 7

5 Taking Modular Storage to New Heights Hitachi TagmaStore Network Storage Controller Model NSC55 A White Paper By Hu Yoshida Business Requirements for a New Modular Storage Architecture Entry-level, midrange, and distributed enterprises require modular storage for a number of reasons. The main requirements are low cost and ease of operation and management. Few of these organizations have raised-floor data centers with operations staff and dedicated storage administrators. In the past, such organizations have been able to trade off enterprise-class availability and functionality, such as nonstop operations and data replication, for lower costs and less operational complexity. They could afford to live with occasional downtime, maintenance windows, weekly backups, and tape restores. However, today s new business drivers regulatory compliance, the widespread impact of operational risk, and greater need for business agility in a real-time economy have changed things. Large and midsized enterprises are increasingly linked in a chain of dependencies. Large enterprises require their suppliers and partners to provide the same level of data retention and data availability as they require of themselves. And, if these requirements are not met, large organizations are likely to seek other suppliers and partners. Today, smaller organizations need the same storage functionality as large enterprises. In fact, they must be even more agile with their IT resources in order to compete. To meet these new business requirements, modular storage must rise to new levels of availability, performance, connectivity, capacity, recoverability, adaptability, and security, while preserving the fundamental requirement for low cost and ease of operation and management. The Hitachi TagmaStore Network Storage Controller model NSC55 gives these organizations the latest in enterprise storage functionality within a modular package. Delivering the advanced features and functionality of the TagmaStore Universal Storage Platform controller-based virtualization, logical partitioning, and universal replication the NSC55 offers packaging, environmentals, and cost, specifically optimized for the modular market space. Operational simplicity is another requirement of this market. The complexity associated with enterprise-class functionality is reduced through the virtualization capability of the NSC55, which facilitates operations such as configuration upgrades, technology refresh, and such advanced functionality as tiered storage management and distance replication, minimizing the need to grow staff as storage demands increase. 1

6 Limitations of Traditional Dual-controller Modular Storage In order to limit costs, traditional modular storage architectures consist of only two controllers, each with their own separate cache memory (as shown in Figure 1). Since cache memory is volatile meaning all data in cache is lost when power is interrupted writes to one controller s cache are mirrored to the other controller s cache, to protect against data loss in the event of a controller failure. Some modular storage systems communicate updates to cache between the two controllers using Fibre Channel technology. Figure 1. Traditional Dual-controller Modular Storage Architecture Fibre Channel Cache Fibre Channel Cache Fibre Channel Fibre Channel D D D D D D P D D D D D D P S Traditional modular storage architectures consist of only two controllers, each with their own separate cache memory. Multiple RAID groups containing data (D) drives and a parity drive (P) are created on the Fibre Channel loops between the controllers. Caches Do Not Share Access to the Disks In a traditional, dual-controller architecture, multiple Fibre Channel loops of disks are connected to both controllers so that each controller has access to all the disks. However, because the caches are separate, disks (RAID group) should be assigned to one controller or the other, and they cannot be accessed from both controllers simultaneously. While some vendors will refer to the two controllers as active/active, each controller is active on a different set of disks. This restricts load balancing across the two controllers, as would be possible on an enterprise controller with a shared global cache. RAID Groups Might Reside on the Same Loop Storage systems are configured with RAID to protect against a single disk failure. The RAID parity group might be mapped across one Fibre Channel loop. Since the disks are dual ported, there is usually a second loop available for redundancy. Otherwise, if a loop fails the entire RAID parity group will be lost, along with all its data. Even with redundant loops, a drawer failure could cause both loops to be lost, in which case data will be lost. Most modular storage systems only provide RAID protection for a singledisk failure. Limited Host-system Connectivity Traditional modular storage systems provide connectivity for two Fibre Channel ports on each controller. Some high-end modular storage systems provide a maximum of four Fibre Channel ports per controller, for a maximum of eight Fibre Channel processor connections per system. These front-end ports must be mode set to serve a specific host platform, such as Sun, HP, Microsoft Windows NT, etc. Although multiple host servers may be connected to one Fibre Channel port, on some systems they must all be the same host platform type. Unlike Hitachi modular storage, other modular storage systems cannot support heterogeneous host platforms on the same front-end ports. Traditional modular storage support is limited to open systems attachment; mainframe attachment is not supported. 2

7 Limited Data Mobility Some modular storage systems provide the ability to create point-in-time copies and perform synchronous replication. However, these functions consume cache and processor cycles, and impact the availability of these already limited critical resources. To avoid impacting other storage users, administrators of modular storage systems sometimes run copy and replication tasks during off hours, when applications are not accessing the system. Network Storage Controller Model NSC55: Presenting a New Modular Storage Architecture The NSC55 is architected with a global cache (as shown in Figure 2), accessed by 32 concurrent processors. The global cache means that every processor connection shares access to the same memory resources, and the storage system does not need to worry about synchronizing multiple cache images. Storage systems with global cache support nondisruptive maintenance and configuration changes, and they can sustain the loss of several processors without the need to stop for repairs. If a problem occurs, the workload can be switched to remaining processors while repairs are being made. This configuration also allows applications to load balance I/O across multiple host ports for improved performance and availability. Figure 2. NSC55 with Global Cache and Crossbar Switch Architecture Storage systems with global cache support nondisruptive maintenance and configuration changes, and they can sustain the loss of several processors without stopping for repairs. Increased Connectivity and Safe Multitenancy The NSC55 supports a maximum of 48 physical Fibre Channel host connections, with two on each of 24 front-end processors. The initial configuration contains two processor boards. On each board there are four front-end director (FED) processors and four back-end director (BED) processors. An optional set of 3

8 processor boards is available; there are eight FED processors on each board for a maximum of 24 FED processors or 48 physical Fibre Channel connections. Each physical host connection can be virtualized, allowing up to 24,576 virtual hosts. Each virtual host connection can be assigned its own private storage address space a Host Storage Domain ensuring no other host connection can see, modify, or destroy data allocated to this host connection. Safe multitenancy means that multiple hosts can share the same physical resources, safe and secure in their own address space. No other storage vendor provides this level of port connectivity and protection. The NSC55 has other processor boards that support IBM FICON for mainframes, and embedded NAS, giving it the widest range of host server connectivity. While mainframes are predominantly data center class systems, smaller mainframe configurations can take advantage of the lower cost and smaller packaging of the NSC55. Write Mirrored Global Cache for High Availability The global cache image is mapped across two physical cache modules that are accessed through a pair of non-blocking crossbar switches, providing redundancy and availability. Writes are mirrored in separate cache modules for cache-write protection. The crossbar switch architecture enables the NSC55 to dynamically switch around failures and hot spots to maintain availability and performance in the event of multiple processor failures. This design provides percent availability, with support for nondisruptive maintenance and upgrades. All the complexity of managing disruptions due to failures, maintenance, or configuration changes including starting and stopping applications and servers is eliminated. This greatly eases the burden of storage management for the operations staff of a small, midsized, or distributed organization, and ensures a higher level of availability. Packaged for the Modular Environment The NSC55 is packaged in a 19-inch rack with front-to-back cooling and 200 volt, single-phase power. This allows the NSC55 to be operated in non data center environments. The packaging, environmentals and low cost are suited to modular environments. Private Virtual Storage Machines for Quality of Service Like the Universal Storage Platform, the NSC55 provides Private Virtual Storage Machines through dynamic cache partitioning, allowing multiple critical applications to run on the same system without one application stealing cache from the other. Each Private Virtual Storage Machine can be dynamically assigned to a host server to ensure quality of service (QoS). The NSC55 supports up to eight Private Virtual Storage Machines; the Universal Storage Platform supports up to 32. Other than the IBM DS8000, which provides two logical partitions, no other vendor offers the ability to ensure QoS with the partitioning of cache. 4

9 Enterprise Data Mobility The NSC55 and Universal Storage Platform use the same microcode. This enables the NSC55 to support the same enterprise-class functionality provided by the Universal Storage Platform. The NSC55 supports Hitachi ShadowImage In-System Replication software for volume mirrors, Hitachi Copy-on-Write Snapshot software for quick recovery, Hitachi TrueCopy Remote Replication software and Hitachi Universal Replicator for TagmaStore Universal Storage Platform for distance replication and business continuity, Hitachi Volume Migration software for volume migration across multiple tiers of storage, and Hitachi Universal Volume Manager software for virtualization of external storage. The NSC55 also supports mainframe functionality through IBM ESCON and FICON connectivity. All advanced functionality available to internal disk capacity is also available to external storage virtualized behind the NSC55. The Value of Virtualization With the optional Universal Volume Manager software, the NSC55 has the capability to attach heterogeneous storage systems, through Fibre Channel ports, and virtualize the connected capacity in cache memory. All capacity, internal and external, appears as NSC55 disks. The ability to virtualize attached storage systems allows entry-level enterprises and smaller organizations to preserve their investment in existing modular storage. Virtualization also allows the advanced functionality supported by the NSC55 to be mapped across less-functional external storage. Point-in-time copies and synchronous and asynchronous remote replication, which could not otherwise be supported on modular storage without a significant impact on controller performance, can be performed using the power of the NSC55 controller. The high-performance global cache and crossbar switch architecture can also improve the native access speed of external storage systems. This reduces the need for software on the external storage and provides common management across heterogeneous storage systems. Unlike other approaches to virtualization, the NSC55 does not add complexity and cost to the SAN or restrict functionality to a single proprietary storage system. The NSC55 enables heterogeneous storage virtualization through the addition of the Universal Volume Manager software. No additional appliances or intelligent switches are required. Attaching external storage to the NSC55 does not require the purchase of additional switch ports to increase connectivity. When external Fibre Channel storage ports are connected to Fibre Channel ports on the NSC55, the Universal Volume Manager software queries the connection using standard SCSI commands. Logical units, attached behind the ports of the external storage systems, are automatically discovered and presented to the NSC55 as though they were internal NSC55 logical units. One of the greatest challenges for the smaller enterprise is the ability to grow data and storage resources with limited IT staff. The NSC55 approach to storage virtualization addresses this challenge through the reduction of complexity and the addition of enterprise functionality to existing modular storage assets. Application data can be relocated, migrated, copied, and replicated without disruption. Virtualization through the NSC55 enables management of the entire storage pool of internal and external capacity, without interruption, through one management tool. 5

10 Highly Available Capacity When and Where You Need It The NSC55 is configured with a 12U-high, 19-inch rack disk chassis, containing up to 60 disks, arranged in four rows of 15 disks; a minimum of four disks and a spare are required in the first chassis. Three optional disk chassis are available for additional capacity. Each chassis has four redundant Fibre Channel loops (eight total), with one redundant loop to each row. Unlike other modular storage systems, RAID groups are striped vertically across loops so that a loop failure will not cause the loss of an entire RAID group. The NSC55 supports RAID-1 (2D+2D), RAID-5 (3D+1P), and RAID-6 (6D+2P). In a RAID-6 configuration, data is striped twice across four rows. RAID 6 uses two parity drives to prevent loss of data in the event of a second failure during a rebuild of a previous failure. The NSC55 supports 76GB, 146GB, and 300GB drive capacities. Although Serial ATA (SATA) disks are not supported for internal storage, SATA-capable storage such as the Hitachi TagmaStore Adaptable Modular Storage and Workgroup Modular Storage systems can be externally attached and virtualized. Since internal and external disks can be added nondisruptively, the NSC55 enables storage managers to buy and provision storage capacity on demand. By eliminating the traditional downtime associated with adding storage capacity, growing organizations are able to take advantage of the historical price erosion of commodity disks, lowering the ongoing cost of provisioning new capacity. A Comprehensive Suite of Storage Management Software Without a means to visualize how resources in a virtualized pool of storage are connected, virtualization can add management complexity. Hitachi HiCommand Storage Services Manager software, powered by AppIQ, provides administrators with visibility into a virtualized pool of storage and supports applicationto-storage-device monitoring, provisioning, and alerting. The NSC55 supports virtualization of external Fibre Channel storage from IBM, EMC, Sun, HP, and Hitachi through the optional Universal Volume Manager software. Movement and migration of data between internal and external storage resources is provided by Hitachi HiCommand Tiered Storage Manager software, which supports the definition of storage tiers and migration groups. Tiered Storage Manager software allows policies to be defined for automated migration of data, based on time or events. Hitachi HiCommand Tuning Manager software provides an end-to-end view of storage capacity use and performance from application to external storage, with the ability to show trending and model projections. This comprehensive set of tools allows entry-level and midrange enterprises to simplify and optimize their management of storage resources. A Clean Green Machine The European Union (EU) directive for the reduction of hazardous substances (RoHS) is intended to protect human health and the environment by restricting the use of select hazardous substances such as lead within electrical and electronic equipment. This directive, which goes by the lengthy title Directive 2002/95/EC on the Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment, will be enforced throughout the European Community beginning July 1, Hitachi Data Systems supports initiatives such as the EU RoHS directive, and the NCS55 is compliant with the provisions of the new law. This position will ensure a safe and clean environment for Hitachi Data Systems customers, and it will avoid future government mandated spending to track and replace noncompliant products. 6

11 Designed to Provide Enterprise-class Functionality Regulatory compliance, business continuity, and business agility are placing tough new demands on the storage environments of entry-level enterprises and fast-growing midsize organizations. These are demands that today s modular storage solutions were not designed to meet. Satisfying the need for enterprise-class availability, performance, and connectivity, without enterprise-scale management complexity and price tag, requires a new approach to modular storage. The NSC55, with 32 processors, a global cache, and crossbar switch architecture, is the first modular storage product designed to meet the new demands facing smaller enterprises and organizations. While the NCS55 can be a standalone replacement for existing storage, it truly excels when virtualizing already deployed resources, enhancing the functionality, performance, and lifespan of these systems. Volume Migration and Tiered Storage Manager software support the seamless movement of data between all virtualized storage, allowing IT staff to do more with less. A radical departure from the traditional dual-controller storage architecture, the NSC55 offers levels of availability, scalability, performance, and advanced functionality previously only available to the largest IT organizations. With enterprise-class functionality and a modular storage price tag, the NSC55 satisfies the increasingly complex demands facing the storage environments of entry-level enterprises and fastgrowing midsized organizations. 7

12 Hitachi Data Systems Corporation Corporate Headquarters 750 Central Expressway Santa Clara, California U.S.A. Phone: info@hds.com Asia Pacific and Americas 750 Central Expressway Santa Clara, California U.S.A. Phone: info@hds.com Europe Headquarters Sefton Park Stoke Poges Buckinghamshire SL2 4HD United Kingdom Phone: + 44 (0) 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. HiCommand is a registered trademark of Hitachi, Ltd. Universal Star Network, TagmaStore, ShadowImage, and TrueCopy are trademarks of Hitachi Data Systems Corporation. All other trade names, trademarks, and service marks used herein are the rightful property of their respective owners. All other 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 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. 2006, Hitachi Data Systems Corporation. All Rights Reserved. WHP January 2006