Charting the future helps users pick the best RAID-based storage solution
Today's technology is continually advancing, particularly in the field of storage and RAID (Redundant Array of Independent Disks) solutions. Developers constantly create new, more advanced ways of managing and controlling information. RAID, a way of storing the same data in different places redundantly on multiple hard disks, has become a necessity. The amount of information and data being stored on hard drives has increased exponentially, along with the need to keep that data accessible. And, the need to have constant access to the data with the ability to update it grows daily. With that need in mind, manufacturers have developed and provided various different solutions to the ever-expanding market. RAID solutions can be used for any need and any level, from desktops and workstations to enterprise servers.Developed by UC Berkeley's computer science department 20 years ago, RAID became a much-needed source of storing data due to the changes in technology and the use of computers. Computers and hard disk drives became faster, smaller and cheaper. The computer became a critical part of an organization's business. More and more data was stored in the computer and this information needed to be available 24/7.
In 1999, host-based RAID units grew 39.8 percent from 1998, which was twice that of multi-user server platform units, and UDMA or IDE RAID cards grew 167 percent from the previous year. Several challenges surfaced in the storage industry, including the need to:
* Improve system I/O performance at the pace of computing performance increases so that access to data did not become a limiting factor for applications; and;
* Provide uninterrupted access to on-line data at levels of reliability in excess of the expected lifetimes of the computer systems that process it.
* Why RAID has become a popular solution:
* The primary server bottleneck continues to be I/O Power, not CPU.
* The Internet industry's continued success depends on I/O throughput (LAN and Disk).
* PC servers are growing into mainframes and minis -- they need to match the I/O.
* The dollar per MB of storage continues to rapidly decline.
As we all know, data accessibility and reliability are essential key factors in today's business world. With more accessible and reliable data comes a price. How much of a price? It depends on the total storage requirement, the type of redundancy, and how quickly users need to recover from a failure. The cost of this hardware should be measured against the cost of system failure and the cost of downtime due to this failure. Some industries can sustain the loss of a disk drive or two and not suffer financially. Others where 24/7 availability is a requirement, such as brokerages, measure revenue loss in minutes of downtime. For this class of customer, RAID with full redundancy is a must-have.
One growing trend in RAID is Ultra l60 SCSI PCI low profile RAID controllers. Low profile PCI is a new PCI card standard for space-constrained system designs that maintain the same PC signals, electronics, functionality, and software drivers as standard PCI expansion cards. Based on the Low Profile PCI Standard (LPPCI) developed by the PCI Special Interest Group (SIG), the low profile RAID controller, targeted for 1 U and 2U servers, allows information technology (IT) managers to save expensive rack space, reduce co-location costs, and increase the available space for RAID storage, routers, and other types of adapters.
In addition to enabling these small rackable servers, the low profile board delivers increased value to workstations and dedicated task servers that have little space for add-in options. The low profile form factor 'meets customers' need for a physically smaller server. Until now, server OEMs desiring optional 110 configurations on their low profile rackable servers needed to mount standard PCI adapters horizontally. In many cases this increased overall implementation costs, limited flexibility, and hampered the ability to provide increased system scalability.
Choosing the best approach to RAID-based storage requires application and requirement analysis, and today's end users and systems integrators are faced with a steadily increasing number of technology choices. Fibre Channel is slowly taking a larger share of the high-end market from SCSI, while less complex and less expensive host-based RAID systems are becoming increasingly attractive to low-end and mid-range users. While new bus technologies continue to improve open storage bottlenecks in speed and other limitations including, cable distance, drive capacity and capabilities, drive prices continue to drop steadily.
