Why You Need to Use RAID When Recording Video

Access Insights News Tagged

Many people either don’t know what RAID is or have only a basic understanding of the technology.  RAID stands for “Redundant Array of Independent Disks”.  It describes the Hard Drive configuration of a PC, Server or Storage Device. Currently there are 7 RAID levels and 6 nested RAID levels. For the purposes of this article we are only going to deal with 2 of the RAID levels and how they pertain to video storage.

Redundancy is the most important aspect of a RAID system. Hard drives are spinning disks that over the course of time are going to fail. It is simply a matter of time before it happens. Hard drives used in video solutions are more prone to failure because they are constantly spinning. A standard hard drive that is in a PC or server only accesses the hard drive when there is a request for information from a user or new information needs to be written to the drive. Over the course of a 24 hour day the actual hard disk usage is a very small portion of the entire day. In comparison a Digital Video Recorder (DVR) or Network Video Recorder (NVR) is always spinning the hard drives, 24 hours a day, 365 days per year. The constant spinning of the hard drive will cause the unit to fail much faster than a hard drive in a PC or a server.

So how does a Video Server overcome the constant usage? The first step to overcome the constant spinning of the hard drive is a quality DVR or NVR. Higher quality devices use “Enterprise Class” or “Server Class” hard drives. These drives are built to withstand higher usage. This is a good step, but the hard drives will still eventually fail.

 The redundancy element in a RAID allows for a hard drive in the system to fail and the video that was stored on the drive to be recovered. So why is this important to a Surveillance Camera system? If you have a hard drive failure, all of the video archived on the drive is lost.  As hard drive capacities have increased, this means more and more stored video will be lost. A week, 2 weeks or even a month of recorded video can be lost instantly with a single hard drive failure. This is why RAID is so important. The two most common RAID levels found in video storage are RAID5 and RAID6. These two levels are very similar. But what they have in common is that if a hard drive fails the video is NOT lost. That potentially months’ worth of video can be reclaimed by replacing the failed drive and the data is rebuilt. A RAID6 level will actually allow for 2 of the hard drives to fail and still all of the data can be recovered.

 If the video recorded is important to you and/or your organization then using RAID storage is a smart choice. By installing a system that does not provide RAID storage, means that it is only a matter of time before you lose your stored video.