Seagate or Western digital

Seagate  or Western digital.

Hard drives! Anyone in the IPCCTV world will tell you these are the only two hard drives that are really used in most digital recorders today. They will also tell you that both are the same , there is no difference, it does not matter which one you use. This is especially true of installers who buy their DVR’s from the manufacturers and install their own hard drives .This can save a lot of money. Most manufacturers will advise against this but all in the know realize that on paper it makes little difference.

But……….

However we have come across a case where it seems some DVR’s really do need the hard drive installed that the product has been tested on. Below we carried out a series of test on a DVR that seemed to fail for no apparent reason the results were surprising and indeed could shed some light onto why DVR’s seem to fail for no apparent reason.

The test.

Below is the findings as described by the technician who carried out the testing…………………….

“I have been undertaking an extensive test on the DVR to emulate some of the issues we are seeing reported in the field”………..

The issues we were hearing were:-

  • Alarms locking up the units
  • Rebooting
  • HDD / recordings missing

I have set up a unit and  over the last 2 weeks, here are the results of my tests:-

Seagate 1Tb ST31000525SV – 2 of them to make 2Tb –  DVR 400ips unit

  • 5 cameras connected (1 camera looped to 4 other inputs)
  • CCTV Camera 1 is set up for motion and also I have turned on Sensor 1 and set to N/O – basically causing the alarm to be permanently on
  • Cameras 2-5 are set for motion
  • Recording schedule set for motion and continuous 24/7
  • Notify set to send alarm data to an internal IP address………….my laptop,……….so not always there (testing to see if a non-connection will cause lockup)

After 1-2 days of me not being present, the unit shows the ‘no HDD’ symbol with a red cross through the symbol………..looking at the System info, no HDD’s are present………reboot and they still do not appear……..when I do a full power recycle, both HDD’s appear again, the system continues recording and all video recording is still present (up to the point where the HDDs disappeared obviously)

last week, I observed the unit reboot after 3 hours, and when I checked the System info, one of the HDDs had disappeared……..a couple of hours later, both HDDs had gone after another reboot

So, I had taken delivery of 2 x Western Digital 1Tb HDDs Caviar AV 10EVDS and proceeded to put those into the  DVR in question

It is now Wednesday (5days later) and the exact same test has been performed with no reboot, lockup or HDD / Video recording loss……………….this leads me to suspect the following:-

  • The Seagate drives we were using were a faulty batch (possible but unlikely)
  • The Seagate drives we were using are actually not fully compatible with the DVR firmware, even though the manufacturer gave us the part number (possible)
  • The Seagate drives were not correctly inserted  by the client and my changing the drives to another unit is purely coincidental and corrected the fault – again  unlikely

Conclusion , it would seem that there is some subtle difference between the hard drives that has caused the DVR to crash although in practice this is not really possible the testing proves that somewhere within the firmware of the DVR a problem has occurred with the original hard drives.

When we at integrated CCTV asked the engineer if he thought there was a difference between the hard drives he replied.

“No same spec should make no difference, hard to understand, the Seagate is a good make so its not the Hard drive just the way it works with the DVR”

Feedback.

Has anyone else experienced hard drive failures on your own DVRs that may in fact be caused by a similar problem? If so we welcome your thoughts and feedback.