No, we’re not talking about the common insect killer that most likely comes to mind. RAID is an acronym for Redundant Array of Independent Disks. With RAID, your servers can remain functional even if one or more disks in your cluster fail.
A standard used in enterprise servers for decades, the original purpose of RAID was combining inexpensive disk drives into an array that would provide a single storage unit with higher capacity, fault tolerance, and increased disk I/O speeds. As the technology has matured, Raid is now being used to ensure redundancy of Network Attached Storage (or NAS) devices. These storage appliances are common in large enterprise network computing environments.
There are several different types of RAID storage schemes available, commonly referenced by their respective mode numbers. The mode numbers essentially indicate the way in which your system administrator has configured the disks to operate. The three most commonly used RAID schemes are RAID 0, RAID 1, and RAID 5. When more redundancy is needed, system administrators may elect to use less common RAID storage schemes as needed. The less common, but sometimes necessary, RAID schemes include RAID 6, RAID 5+1, RAID 10, and JBOD — short for “just a bunch of disks”, it allows your sys admin to rapidly construct storage redundancy to their organization’s precise specifications.
There are other schemes, including Microsoft’s virtual disk RAID, Netgear’s X-RAID, Drobo’s BeyondRAID, and Synology’s SHR. These are available on the market now, and you may find them useful or necessary within your enterprise.
However, these less common RAID storage schemes simply won’t be in use as much as the top four, so those are the ones we’ll focus on today.
Why should you use RAID? Well, in short, having a redundancy setup on the hard drives of your servers could potentially save your business from costly downtime. Many IT professionals refer to RAID as disk failover protection or “fault tolerance”. With RAID, your organization could lose a disk within the array without it affecting operations or even missing a beat. Most RAID arrays provide admins with SMART disk stats, which will alert the IT staff if a drive is about to fail within a RAID cluster.
Keep in mind that RAID provides protection against faulty hard drives, but it’s not an insurance policy against other potential computing issues that may arise. RAID doesn’t protect your business against data loss that might occur due to malware, accidental file deletions, or natural disasters. RAID is simply a fail-safe for hard drive failures. It’s not configured to work as a substitute for proper data backup practices.
All RAID levels apart from RAID 0 offer single-drive failure protection, while RAID 6 can be configured to stay online even if two disks fail simultaneously.
Typically used in servers where fault tolerance is required and data accessibility is truly critical, RAID is commonly used on network-attached storage devices and servers that host critical line-of-business applications.
RAID is available for use on desktop PCs. Businesses that build high-powered desktop PCs for their employees (such as those in the CAD or multimedia editing fields) may benefit from setting up RAID in their desktop PCs. RAID will provide a robust disk I/O while simultaneously providing hard drive fault protection when the PC needs to be able to store mass amounts of data locally.
RAID 0 offers no fault tolerance as the data is striped across 1 or more disks without protection against failures. RAID 0 is typically used in machines that wish to bridge together one or more disks to maximize storage space. By contrast, RAID 1 is a mirrored disk configuration. So, if you had 4 disks working in a RAID 1 configuration, two disks would simply mirror the other two disks. If one disk fails, RAID 1 switches over to the mirrored copy of the disk, providing a level of fault tolerance. However, it is significantly slower when compared to RAID 5 and RAID 6.
What about RAID 5 and RAID 6? Most small-to-medium sized enterprises elect to use RAID 5 or RAID 6, or even RAID 10. These are ideal for IT professionals working within limited budgets who need to get the most out of the disks in their array.
With RAID 5, your business can afford to have one disk completely fail, and the array will operate as though nothing has happened. RAID 5 requires at least 3 physical hard drives for configuration. With Raid 6, on the other hand, two disks in your array can fail without the server’s storage platform failing. RAID 6 may run slower than RAID 5, but many storage architects continue to prefer it due to the extra redundancy built into its storage scheme.
With the rapidly declining costs of SSD hard drives, many storage administrators are beginning to configure SSD hard drives into RAID configurations. These high powered storage arrays provide extra speed for businesses that need their servers to perform at their peak performance.
As SSD prices continue to decline, more businesses will begin using SSD hard drives to build out their RAID storage arrays in order to gain an edge on their competition.
At BACS, we provide high-tech Managed IT and Security Services to everything from small startups to large enterprises nationwide from our base here in the San Francisco Bay Area. Whether you’re looking for protection against ransomware, data protection services, IT support, or are looking for a consultant to take a look at your network and let you know where the weak spots are or what could be done to get your business moving faster, we’re here to help! Reach us by phone at (650) 887-4601 or contact us online at any time!
Published on 30th August 2016 by James Berger.