I don't know if this is the right figure to use, but is there a general threshold over which you definitely need an HDD purposed for surveillance?
Thanks,
John
Thanks,
John
How many MP until I need a purple drive?
- Thread starter frankred
- Start date
The number of cameras and the bit rate of the cameras are what matters in this case. Megapixels doesn't mean anything to the storage device.
Anyway, any threshold someone gives you will just be a guess. Most hard drives are perfectly fine for video recording even from large numbers of cameras and high bit rates. My guess is you'd have to be into the hundreds of Mbps (megabits per second) before you would likely see a benefit of a WD Purple drive as opposed to a Red or Blue or Green or anything from any other manufacturer. In some cases (like if the alternative is a solid state drive or a really nice RAID array with a good controller) a Purple might actually perform worse.
That said, for continuous recording, some low end drives might wear out faster and fail prematurely or run into intermittent problems like taking too long to recover a bad sector and causing your recording to be temporarily interrupted. Or maybe they'll go to sleep after a period of inactivity and take too long to spin up again (though most software should be able to handle this situation). WD Purple drives don't cost too much more than any other type of drive so generally we just recommend them to everyone looking to buy a drive for video recording.
Anyway, any threshold someone gives you will just be a guess. Most hard drives are perfectly fine for video recording even from large numbers of cameras and high bit rates. My guess is you'd have to be into the hundreds of Mbps (megabits per second) before you would likely see a benefit of a WD Purple drive as opposed to a Red or Blue or Green or anything from any other manufacturer. In some cases (like if the alternative is a solid state drive or a really nice RAID array with a good controller) a Purple might actually perform worse.
That said, for continuous recording, some low end drives might wear out faster and fail prematurely or run into intermittent problems like taking too long to recover a bad sector and causing your recording to be temporarily interrupted. Or maybe they'll go to sleep after a period of inactivity and take too long to spin up again (though most software should be able to handle this situation). WD Purple drives don't cost too much more than any other type of drive so generally we just recommend them to everyone looking to buy a drive for video recording.
Thanks for the feedback BP! I will be running a SSD for an OS and whatever 500gb drive is coming in the HP Elitedesk G1 800 for storage. I will run this for a short while before determining which larger drive to get to replace the 500...
nayr
IPCT Contributor
a purple is the exact same hdd as a red, physically.. the difference is in the firmware/software.. Red's Firmware is Optimized for NAS performance, Purple's firmware is optimized for NVR Performance.. they have different load cases. (RAID vs JBOD) and the Purple has been optimized for multiple continuous, never ending writes.. dont matter how many cameras really.. where as NAS disks have to balance the need for decent random read/write performance, something a NVR has no need for.
pay the few dollars more and get a purple, storage is never the place you want to skimp and save some cash.. the only reason you can get the RED's cheaper is simply volume, there are a million more NAS's out there than NVR's.
One of my childhood friends is now writing the firmware for WD HDD's and we've discussed this extensively..
pay the few dollars more and get a purple, storage is never the place you want to skimp and save some cash.. the only reason you can get the RED's cheaper is simply volume, there are a million more NAS's out there than NVR's.
One of my childhood friends is now writing the firmware for WD HDD's and we've discussed this extensively..
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Zorac
Getting the hang of it
- Apr 17, 2015
- 213
- 26
if you run them wiht continous writes wont get much more than a year out of the cheap ones. i write roughly 3mbits/sec continously 24/7 and i was wearing out seagate 3tb consumer drives in rought a year (cooked two of them before i gave that up). im running wd reds now and will see how well they last. actually went in for purples, but the store didn't have them in stock and i needed something now so i went with reds.
That sounds like interesting discussion. I have looked for a few minutes, I am drawing a blank on finding the name of the software people use to change Greens to Reds. I think it has something to do with parking heads. Is there something similar to change to Purple (from a black, green, or red)?
nayr
IPCT Contributor
the software is on the circuitry embedded onto the bottom off the hdd, with the proper tools you could probably flash new firmware onto the chip with the right hardware and a binary copy of the firmware.. but where you'd get that copy and why you'd obviously destroy the warranty so blatantly is a mystery.
there are other things that go into selecting the components, you get what you pay for.. think of it like this, every 1.5TB platter they make, there trying to make a top of the line enterprise SAS drive... but when it goes through QA any bad sectors or defects get it downgraded to a consumer platter, with less warranty and smaller price tag to reflect this.. all the defects will be identified in manufacturing and hidden from any tools that would report them.. the things are so sensitive that a perfect platter is rare and the majority get downgraded, this is why a high end enterprise disk with a 5 year warranty and a much better MTBF rating costs so much more.
Red/Purple are likely the same grade.. Green is a grade lower and RedPro a grade higher.
there are other things that go into selecting the components, you get what you pay for.. think of it like this, every 1.5TB platter they make, there trying to make a top of the line enterprise SAS drive... but when it goes through QA any bad sectors or defects get it downgraded to a consumer platter, with less warranty and smaller price tag to reflect this.. all the defects will be identified in manufacturing and hidden from any tools that would report them.. the things are so sensitive that a perfect platter is rare and the majority get downgraded, this is why a high end enterprise disk with a 5 year warranty and a much better MTBF rating costs so much more.
Red/Purple are likely the same grade.. Green is a grade lower and RedPro a grade higher.
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whoslooking
IPCT Contributor
The purple drive is designed to continually write, without sleeping, the other drive are not, they will spin down and rest when not needed, partly sorted in the embedded firmware and part in spindle.
always buy the drive fit for the job it was designed for.
always buy the drive fit for the job it was designed for.
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