RAID - Redundant Array of Inexpensive (or sometimes "Independent") Disks - is a method of combining several hard drives into one logical unit. It can offer fault tolerance and higher throughput levels than a single hard drive or group of independent hard drives.
RAID is a mature technology that speeds up data access while at the same time protecting your data from hard disk failure. RAID is quickly becoming a necessary component in every network since data loss and downtime can prove both fatal and financially destructive. Most networks are designed to provide instant access to massive amounts of data. More and more employees have to access customer and other databases. Intranets and corporate Web sites provide access to huge databases online.
Benefits of RAID
RAID provides increased storage capacities, and protects your important data from hard drive failure.
There are multiple benefits of using RAID:
- Real-time data recovery with uninterrupted access when a hard drive fails
- System uptime and network availability
- Protection against data loss
- Multiple drives working in parallel increase system performance
A disk system with RAID capability can protect its data and provide on-line, immediate access to its data, despite a single disk failure (some RAID storage systems can withstand two concurrent disk failures). RAID capability also provides for the on-line reconstruction of the contents of a failed disk to a replacement disk.
RAID offers faster hard drive performance and nearly complete data safety. Storage requirements are expanding as file sizes get bigger and rendering needs get more complex. If you handle very large images or work on audio and video files, faster data throughput means enhanced productivity. RAID can be backed up to tape while the system is in use.
The most common RAID levels, listed below, each exhibit their own unique benefits and drawbacks. This overview will attempt to highlight each or help you find the right RAID level for your particular application. Please note that the numbers assigned to each level of RAID are not indicative of superiority, they are merely for differentiation.