Hard drive failures will render even the most sophisticated surveillance system useless. Without a working HDD, it is impossible to store and then retrieve the video footage.
Hard drive failures will render even the most sophisticated surveillance system useless. Without a working HDD, it is impossible to store and then retrieve the video footage.
C.N. Chu, Sales Engineer in
Seagate Technology spoke with
a&s about the factors leading to hard drive failures and how these issues can be avoided. Chu pointed to two major issues that cause hard drive failures: focusing on price and choosing the wrong hard drives for the project.
Chu noted that as much as systems integrators don’t want failures, their customers might still be cost-sensitive. Some of them might end up choosing PC hard drives for surveillance systems, which can cause failure under the more demanding conditions of constant video surveillance. “Many used to think that the cause of failure is the HDD whenever a failure occurs,” said Chu. However, this is not the case.
“In the early days of switching from tape drives to hard drives, the perception of the HDD was the same. We did a study to understand the users’ pain points and realized that the problem was lack of IT knowledge. For example in the beginning there was no air conditioning in the rooms and as a result the HDD would fail a lot. 10 years ago, through market education and explaining how to create an environment suitable for surveillance HDDs, our customers were able to reduce the fail rates from 5 percent to 0.3 percent,” said Chu.
However, despite over 10 years of market education, there are still many aspects of HDD maintenance and handling which are not widely known.
“One size doesn’t fit all in surveillance storage. Every surveillance solution requires different architecture and surveillance recording requirements,” said Chu. To minimize these risks, clients should thoroughly think about the system requirements they need. How often will cameras be running and recording? How long do they need to keep the footage? Where will the data be streamed and stored?
Choosing the right storage system
Single drive systems typically support up to 16 cameras. The new generation of hard drives addresses the need for high-resolution cameras and higher camera counts, large storage capacities and always-on recording. “For entry level deployment: a small retail business could be using a simple embedded NVR or DVR connected to eight to sixteen cameras. The video retention period normally ranges from two weeks to one month, and the requirements of recordings are not as stringent as compared to larger scale projects. In this case, a basic surveillance drive will do the job,” explained Chu.
In higher-end deployments, for example, city surveillance projects in which thousands of IP surveillance cameras are connected to a control center, more sophisticated solutions are needed to support the high number of concurrent video streams. In these cases, enterprise capacity HDDs are needed.
Factors leading to system failures
According to Chu, hard drives are often blamed for surveillance system failures. “The cause of these failures can sometimes be traced to the power supply. Computer power is not the same in every system and sometimes the power supply unit that comes with the DVR is too weak to support three or more HDDs. I personally recommend using power supplies of three Ampere to make sure that the HDDs get enough power to run properly. Some entry level DVRs support 2A power which isn’t enough for three-disc capacities. But it’s hard for consumers to identify the reason.”
“In addition, it is also important to do preventive maintenance of the DVR at least once a year. Opening it and brushing away any dust that has built up inside will also help the system run smoother and decrease the chance of failure due to dust affecting static electricity and oxidization,” added Chu.
Sometimes, it isn’t the drive that is the cause of failure, “cheap entry level DVRs/NVRs with an arm-based SOC can’t handle high frame rates, causing failure in recording or loss of frames, or sometimes the camera capacity can’t support high frame rates. All these may lead to dropped frames,” said Chu.