EMC AX150 Product Guide - Page 4

Executive summary The EMC® CLARiiON® AX150 provides small to medium-sized businesses with a new, affordable, easyto-use storage platform. This platform offers improved connectivity and availability, expanded easy-to-use software to manage the storage systems, and improved I/O performance featuring command queuing, faster interfaces, and increased storage capacity. The AX150SC, which has a single controller, is almost identical to the AX150, which has two controllers. In this paper, descriptions of the AX150 apply to the AX150SC, except where noted. The purpose of this white paper is to outline the features and functionality of the AX150 and AXS150SC storage systems. The following sections describe: Š The hardware architecture. Š High-availability components. Š Customer-replaceable units. Š Software features, including snapshots for backup and EMC Navisphere® Express for management. Š Connectivity and configuration options. Comparisons between the AX Series and the EMC CLARiiON CX Series storage systems are made where appropriate. Intended audience This paper is intended for customers or internal EMC personnel who desire a brief technical description of the AX150 storage system and its features and functions. Terminology The following terminology appears in this white paper: Cache ― high-speed memory within the storage system that stores most-recently-accessed data. To yield faster response times, all host writes are written directly to cache and are acknowledged, rather than being written to disk. Cluster ― two or more computers managed by software that allows the computers to access the same data and be presented as one host for the purpose of parallel processing, fault tolerance, or load balancing. Disk pool ― in AX150 terminology, disk pool is interchangeable with the term RAID group. It is a collection of fault-tolerant disks that are carved into virtual disks. Fibre Channel ― a high-bandwidth data-transfer mechanism that uses optical cables to connect devices and is designed for high-performance storage systems. Host bus adapter (HBA) ― A card resides on the server to manage the transfer of I/O, and to act as the interface between the computer's internal bus and the Fibre Channel connection. Redundant Array of Independent Disks (RAID) ― a collection of disk drives that are presented to the host as one entity. Data is distributed across these disks to increase fault tolerance and performance. The AX150 supports RAID level 5, which provides striping of the data and error-checking information across a minimum of three disks. It also supports RAID 1/0 groups with a minimum two-disk configuration. Serial Advanced Technology Attachment (SATA) ― an enhancement that uses thinner cables and provides better performance over parallel drive technology. Server ― a computer on the network dedicated to performing a specific task, such as running a particular database or mail application. The storage necessary to run these applications often resides on a storage system within the SAN. The server is sometimes called the host. Storage area network (SAN) ― a high-speed Fibre Channel subnetwork that makes all storage devices visible to servers. Introduction to the AX150 Storage System A Detailed Review 4