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Reliability of HDD vs Solid State

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If you are building an NVR server and have a separate drive(s) for video, which is considered more reliable for the OS drive, an enterprise HDD or enterprise SSD? Have you used an SSD in an NVR, and if so, which one do you prefer?

 

Best,

Christopher

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I always hear that SSDs have a limited write capacity. With the amount of writing a DVR/NVR system will be doing, I'd lean towards the traditional hard drive. If write speed is a factor, consider a RAID 5 or 6 system, which will provide a higher write speed as well as redundency.

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With the amount of writing a DVR/NVR system will be doing,

 

The video is written to another drive(s). I'm referring to the drive for the OS.

 

Best,

Christopher

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With the amount of writing a DVR/NVR system will be doing,

 

The video is written to another drive(s). I'm referring to the drive for the OS.

 

Best,

Christopher

 

That's what I get for thinking you were talking about the data drive. Apologies.

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Ive had my EEE PC for almost 4 years and it uses a cheap SSD.

Granted I dont use it every day but it has less writes than newer and faster SSDs and its still working fine.

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If you are building an NVR server and have a separate drive(s) for video, which is considered more reliable for the OS drive, an enterprise HDD or enterprise SSD? Have you used an SSD in an NVR, and if so, which one do you prefer?

 

Best,

Christopher

 

 

hi. another to consider is a DOM drive. much cheaper than SSD.

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If you are building an NVR server and have a separate drive(s) for video, which is considered more reliable for the OS drive, an enterprise HDD or enterprise SSD? Have you used an SSD in an NVR, and if so, which one do you prefer?

 

Best,

Christopher

 

 

I would go with solid state. There is no moving parts and they tend to last longer than any platter base hard drive.

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We've been having alot of SSD's die on us for some reason. There's definitly certain brands to avoid, I don't recall which ones our IT guy mentioned though.

 

I've heard both good and bad. Don't know if this is a common failure, but I've been told that when some fail, none of the information on the SSD can be retrieved. It's probably a combination of a maturing technology and vendors to avoid.

 

Best,

Christopher

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For over a year, we are using SSD drives for OS and applications and SATA drives for storage most of the time. In few occasions, we built a complete SSD based solution, including storage... extremely expensive, but there is a limited market out there.

 

Besides, SSD pricing has been coming down and chances are very good that in few years, most of the hard drives will be available on SSD format.

 

We mostly use OCZ SSD drives. Used Intel, but serious issues - and very limited support from Intel.

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Personally, I will never buy another computer whose OS is running on anything other than SSD. I recently re-built an older Dell Inspiron 6000 laptop, using one of these SSD's designed for pre-2006 computers. The laptop is now AMAZINGLY fast. But the REAL reason I use SSD's is reliability.

 

MeanTimeBetweenFailure: 2,000,000hrs

That is over 200 years!!!

 

Compare THAT to ANY ENTERPRISE level drive!!!

 

They also have solved the read/write lifetime performance decline that plagued previous SSD's

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Modern hard drives are typically rated for a million hours MTBF (mean time before failure), and they'll do that, provided you look after them (no moving them around, keeping a fan on them so they don't cook, no huge hot/cold temperature swings etc).

 

They're also good for linear reading and writing at up to about 90-100MB/sec; random reads/writes you're looking at about 100 seeks a second - thus, not so good if you're dealing with a ton of small files. CCTV is almost always linear reads/writes of huge amounts of data, so often times regular 7200rpm 1-2TB hard drives are absolutely fine - providing they're in well conditioned environments.

 

SSDs are insane; read more about how and why at the following link:

 

http://www.codinghorror.com/blog/2011/05/the-hot-crazy-solid-state-drive-scale.html

 

In short, they're usually at least twice as fast for reading and writing in linear workloads, and are about 100 times faster when dealing with tons of tiny files - as they can typically manage several tens of thousands of seeks per second. This is a big deal in applications like heavily used databases, caches, and thumbnails.

 

SSDs are a LOT more robust when it comes to temperatures, and being knocked about - HOWEVER there is a significant gotcha, which is their limited lifespan. If you run an SSD at it's rated maximum read/write rate, you'll probably get 9 months to a year out of it before it randomly dies - taking all your data with it. You can read more about this in the article linked above. The MTBF on SSDs, unfortunately, do not take into account this 'continuous read/write' consideration - it's usually on the overall assembily with either no or light usage. Read the specsheet on how they measured it to be sure.

 

None of this takes into account RAID, which if you don't want to lose data is a MUST. Raid 1 - aka 'mirroring' - should be an absolute requirement for you if you can't afford to lose your CCTV data; even MORE so if you're using an SSD, due to their aforementioned tendency to throw their toys out of the pram when they've had enough.

 

In your case, you're probably best going with two 1TB or 2TB 7200rpm drives from a manufacturer you trust (I use Western Digital's Black range, but like all decisions, it's a personal preference these days), and stick them in raid 1 and configure your RAID subsystem to email you when a drive dies.

 

Oh, one more thing - an 'enterprise' hard drive is just one which has had it's label changed, it's seek timeout (how long it'll click-click-click and retry trying to read data) dropped from 60 to 10 seconds, and a price tag of two to three times the regular price stuck on it.

 

One place I work at has over 400 western digital drives in use, and you'll always get a 2-5% failure rate on all hard drives in the first year, regardless of manufacturer. Our SSD failure rate in the first year is under 1%; however on our busier customer's servers it's almost 25% after the first year. We expect to lose another 30-40% of them in the next year on the busy machines that are thrashing the hell out of their SSDS - so again, unless you're dealing with tough environmental conditions, I still recommend regular hard drives in RAID.

 

let me know if you're looking for specific recommendations or advice; I build and maintain servers in a datacenter, so I tend to get a lot of exposure to when things go wrong.

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There is a general misconception about MTBF Mean Time Between Failures.

 

The hands down most reliable Hard Disks are the Hitachi Enterprise Ultrastars. Independent tests have placed them about three times more reliable than the next best. If anyone disputes this, I will hunt down the report that specifies that stellar performance.

 

MTBF for the Ultrastars is as high as 1,200,000 hours. This does not mean that the average Ultrastar will last that long. What it means is that, if you take 1200 Ultrastars and run them for 1000 hours each, that statistically, one of them will fail. Put in that light, even these most reliable Hard Disks appear vulnerable to random failure.

 

As a side note, I imported 2 A7K2000s (2 Terabytes) from the US a while back, and one was DOA.

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The hands down most reliable Hard Disks are the Hitachi Enterprise Ultrastars. Independent tests have placed them about three times more reliable than the next best. If anyone disputes this, I will hunt down the report that specifies that stellar performance.

Toms hardware doesn't live in a country where power spikes and brownouts are daily practice.

However I would agree that the Hitachi in general have lasted well here, but over all the most common hard drive here that gives little to no issues are ofcourse the Western Digital Drive. That said brand means little, as long as the hard drive is on a Voltage Regulator it can last for years. If its not on one of those, then no wonder you guys have failures.

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As I am sure somebody will argue the point, here is the study:

 

http://www.tomshardware.com/reviews/hdd-reliability-storelab,2681.html

 

"we also need to make very clear that the study is not representative and cannot be seen as a comprehensive reliability summary. It reflects only a very tiny fraction of the hard drive market."

http://www.tomshardware.com/reviews/hdd-reliability-storelab,2681-2.html

 

 

A Russian study by a company called Storelab.

Yeah ... I'd really rely on that .. what with all the failed hard drives in my country being shipped to Russia ...

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Disclaimers are common even amongst the most diligent studies. For anyone who has a clue, it is a waiver that legally indemnifies the report against litigants. The MTBF is also an area subject to litigation due to the sensitivity and duty of care impiled in critical data storage.

 

The Vertex SSDs have a MTBF of 2,000,000 hours.

The cost of SSDs is about 15 times that of Enterprise drives per unit of capacity. i.e. per megabyte

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Bugger off num-chucks and cease and desist stalking.

 

Disclaimers are common even amongst the most diligent studies. For anyone who has a clue, it is a waiver that legally indemnifies the report against litigants. The MTBF is also an area subject to litigation due to the sensitivity and duty of care impiled in critical data storage.

 

The Vertex SSDs have a MTBF of 2,000,000 hours.

The cost of SSDs is about 15 times that of Enterprise drives per unit of capacity. i.e. per megabyte

 

what's been plaguing ssd's isn't the actual disk, but the controllers can fail at any time, making the 2,000,000 hours thing useless.

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That may well be the case. The issue of MTBF is taken very seriously by Banks and Financial Institutions and other facilities which may be devastated by the loss of data. If it could be proven that a Hard Disk manufacturer exaggerated the MTBF of its disks, the liability for data loss would be subject to litigation.

 

If anything, I suspect that the MTBF is a very conservative figure.

Controller failures from an onboard chip would have to show up in the MTBF figures, so that when SSDs have controller failures, these anomalies must form part of the overall MTBF. A manufacturer could not make excuses if any part of its HDDs or SSDs failed.

 

On a slightly disquieting note, Hitachi has sold its hard disk division for $4.3 billion to Western Digital so the era of the great Enterprise Ultrastars may be almost over. As the performance, price and reliability of SDDs improves, the future of storage looks bright. The SSDs use less power, have 20X the shock resistance and much faster access speeds for read and write.

 

The high price of SSDs in conjunction with their higher performance has seen their widespread implementation as Boot Disks.

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With the amount of writing a DVR/NVR system will be doing,

 

The video is written to another drive(s). I'm referring to the drive for the OS.

 

Best,

Christopher

a best is a hybrid system with both drives - with the OS on the SSD for max speed

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Just a few days ago I build a DVR and the OS was supposed to run on an SSD (OCZ Vertex Plus). My only worry was that the DVR Software that I use (NetvisionDVR) features an instant playback and I am not sure where these files are actually saved. If the files for the instant playback (8 minutes multiplied by 16 cameras) are saved in the programs folder of Netvision this might shorthen the lifetime of the SSD considerably.

 

Anyhow, I was not able to finish the installation. It broke off every time. Somehow XP didn't like the SSD and the RAID controler that I used. I ended off using an HDD instead.

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The OCZ Vertexes appear to be optimised to function as Boot Disks on computers. I use Windows XP SP2 on my OCZ SSD and it dramatically improved the speed and performance of a Quad Core 2.4ghz. For DVRs I'd stick with the HDD because there is no practical benefit to be gained by using the SSD. They are still way too expensive for general storage and recording purposes. And they are only marginally more reliable than the best Hard Disk Drives which are the Hitachi Ultrastars.

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The OCZ Vertexes appear to be optimised to function as Boot Disks on computers. I use Windows XP SP2 on my OCZ SSD and it dramatically improved the speed and performance of a Quad Core 2.4ghz. For DVRs I'd stick with the HDD because there is no practical benefit to be gained by using the SSD. They are still way too expensive for general storage and recording purposes. And they are only marginally more reliable than the best Hard Disk Drives which are the Hitachi Ultrastars.

 

 

You are right that there is no real benefit on DVRs except for more reliability. I actually bought the SSD, because it was cheaper than the cheapest HDD. It was only supposed to contain the OS and the DVR Software, so I bought a cheap 30 GB SSD. Actual recording was supposed to be on another 2TB drive.

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