View Full Version : Opinions on HD eSATA Storage please.
Michael Lyas November 7th, 2007, 09:35 PM Hi.
I run a fledgling Video production company here in Australia. I'm getting work and inquiries via word of mouth, which is good. I still work 3 days a week at another job.
I'm becoming less enchanted with my results from using SD on Sony Z1P cameras that i hire. -> I'm thinking I've gotta go HD.
I've been researching eSATA storage systems to accomodate such a move.
It appears that for around $AU600 - $AU1500 you can buy a 4 bay enclosure unit that will allow you to run RAID 0,1 and JBOD format.
In my reading, it appears that for a more secure system in relation to data storage, RAID 5 appears to be the go.
My question is, how reliable are RAID 0,1 and JBOD compared to RAID 5?
The price of a unit that can be striped with RAID 5 appears to jump in cost by about 75% ie $AU3500 to $AU6000
I'm thinking that if RAID 0,1 and JBOD is so unreliable, why do they bother?
I look forward to anyones experience.
Thanks
Michael
Chris Soucy November 7th, 2007, 10:31 PM Where are all you Aussies suddenly appearing from? Don't see one for months and then all of a sudden dozens turn up at once!
To the question.
Your average, decent quality hard drive is very reliable. I've never had one fail, nobody I know has had one fail.
Raid 0, where you are multiplying your odds of a failure taking you out, is, purely on the maths, more inherantly unreliable than a single drive.
However: The purpose of Raid 0 is to give you greater HD throughput when actively editing & rendering video. It is not designed, nor required, for archiving raw material or completed projects.
Completed projects are better transferred to semi - offline drives (where duplicates can be maintained) for access at a later time if needed.
For an enterprise that requires all the data to be accessible all the time, at high transfer rates, that cannot tolerate a drive failure impingeing on the workflow, Raid 5 and similar settups are worth the horrendous expense involved (we're talking Banks, Flight Reservations stuff here)
I cannot see that your enterprise falls into that category.
A decent system with a Raid 1 (Mirrored) Operating system dual drive setup, a Raid 0 striped set of drives for active editing and project manipulation, and as many semi - offline external drives as are warranted by the edit/ project volumes, should be ample.
You can go to the expense of Raid 5 etc for the "active component" if you have the pockets for it, but that comes down to a hard commercial decission - will the loss of my "work in progress" bankrupt me?
(This does assume that a rational and regular backup regime is in place to ensure "in progress" isn't left languishing for weeks/ months just on the R0 system).
In short, Raid 0 systems are not "so unreliable". They have a greater chance of failure than a single drive because there are more of them. If you work flow and practices take this into account, a great deal of work can get done safely and efficiently without racking up Ghana's (or Australia's) National Debt for a better system.
CS
Michael Lyas November 7th, 2007, 11:26 PM Here shows my ignorance. I understand the concept of faster access to data of RAID 0, ie the more drives the faster acces to data it is and I think I'm right when I say that RAID 1 mirrors two drives and replicates the same information on each drive and must be used in pairs, but slows down access to data
When you say back up the data for a project, do you mean that I capture footage twice, eg once to the eSATA enclosure and once to an external HD?
ie, how does one back up data when using a eSATA system versus my trusty external firewire drives that I use for Standard Definition work that I do now? Incidentally, for what it's worth I use a Mac and FCP
Thanks for your input.
Michael
Kevin Shaw November 7th, 2007, 11:43 PM RAID is useful but not required for HD editing with HDV or DVCProHD source material. Just get some large, fast eSATA drives and keep a duplicate set if you're worried about backups. Even single USB2 or firewire drives will work if you don't stack up too many layers of video and try to play that in real time.
Chris Soucy November 8th, 2007, 12:24 AM Nope, what I was saying in my usual roundabout way was this.
Capture to whatever you wish, but it doesn't have to be to a raid system. Capture of DV / HDV works fine to any external drive practically. Copy a version to yet another external drive (I mean via the Mac system, not another capture, no dramas, doesn't take long).
When you want to get serious, import to your Raid 0 and have at it. When you've finished, or intermediate, take a copy back out to external etc.
Kevin is completely correct, Raid 0 is not required on modern drive systems for anything to do with DV/ HDV, but it CAN make stuff a lot faster, and time is money, if you're charging for it.
At the end of the day, if you're doing this as a business, you need to make the decision: Trade - off : investment cost = faster throughput.
If the throughput works on a bog standard system, why make the investment?
Again, this is always accompanied by the standard "get out clause" - fail to back up at you peril!.
Has that made it any clearer?
CS
PS: You haven't shed any light on my question. Just where have all the Antipodeans suddenly appeared from (yeah, yeah, the Antipodes, natch) but why? I and a few other hardy souls have been running a furious Oceania rearguard action for ages, all of a sudden there's a rush of new recruits, ready and eager to jump in - but why? How come? What happened?
DVinfo do a commercial run around Australia & NZ? (Can't have been NZ, else I would have seen it, I think)
Just exeedingly curious.
Tim Polster November 8th, 2007, 08:21 AM Well, JBOD (just a bunch of drives) is fast enough for HDV/HD work.
eSATA will get at least 50MB/s transfer rate where DVCPRO HD 100mb/s (mega bits) was recently shown to me to be at ~12 MB/s (mega Bytes).
Your processor is the more important piece of equipment for HD editing.
So I don't see the need for RAIDs in "normal" editing.
If you have more than one camera, just make sure to put a camera per drive to lessen the load.
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