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Which RAID storages for self-employed and small companies ?

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(@zul22)
Posts: 53
Trusted Member
Topic starter
 

Hi,

When I finish the data recovery for some RAID system, I'm often asked which better storage for the future.

The fact is that self-employed people and small companies are often frustrated after their RAID failed, as they had hoped in some security for their data when they purchased such storage, either NAS or USB attached storage.

The price of a data recovery for such storage is commonly higher than thus for a single hard drive.

My experience is

- Most storages that non-specialists purchase use cheap hard drives that are not "enterprise-grade". For instance the WD MyBook Studio uses WD Green drives. The Netgear ReadyNAS Duo uses Seagate Barracuda drives.

- The way data are stored is often poorly documented and to perform a data recovery you have to guess and hack.

- Some systems use "proprietary RAID", like the X-RAID for the Netgear ReadyNAS Duo

- Some NAS use the ext3 filesystem which makes data recovery impossible or very uncertain because the files with their names can only be recovered from the journal.
This is for instance the case with the Netgear ReadyNAS Duo.

- Some storages, especially those for Mac users use the HFS+ file system, which limits the number of available data recovery tools available on the market, although things are improving. For instance, I've seen HFS+ being used by Buffalo and Western Digital.

- RAID 5 can mean more reliability but also more expensive data recovery if a problem occurs.
Just the fact from connecting all drives can be a problem depending on the motherboard.

My preference is to save on several single hard drives and have personal discipline.

RAID 1 also appears me a good choice, but you have to care from the beginning about the file system used, so that you're ready for a possible data recovery.
When possible, I prefer to purchase the drives independantly from the storage.

So, here's my little survey about NAS and RAID storages

1) Which brands, line of products, models do you recommand and for which reason (build quality, reliability, file system used, a.s.o.) ?
2) Which brands, line of products, models would you avoid and for which reason ?
3) Are there using (true) RAID-1 ?
4) Which file system do they use ?
5) Do they accept normal drives or only low powered ones?

Thanks for sharing your experience.

 
Posted : 11/11/2014 6:36 pm
jaclaz
(@jaclaz)
Posts: 5133
Illustrious Member
 

As I see it there is (among the less technical users) a "wrong" (or if you prefer "old/outdated") perception of what RAID is and what it is good for.

RAID 5, 6 or 10 (anything below is IMHO pretty much not useful/reliable) is a solution for having no (or very little [1]) downtime and NOT a solution to secure data (which is redundant backups on different, physically separated media).

RAID 1 is an excellent "simple" solution, but not "enough", as (BTW like the more complex RAID setups mentioned) there are a couple caveats that make it far from "secure", basically a same PSU (and case and connection) is shared and in the case of an electrical "zap" both disks are likely to get fried.

The issue is (still IMHO) what I call "data greed" 😯 , with the huge increase in disk sizes RAID is becoming increasingly more risky, it is several years that a few people are trying to send this message, that regularly is not listened to, *like*
http//www.enterprisestorageforum.com/technology/features/article.php/3839636/RAIDs-Days-May-Be-Numbered.htm
http//www.storagenewsletter.com/rubriques/market-reportsresearch/why-raid-dead-for-big-storage-cleversafe/
http//www.zdnet.com/blog/storage/why-raid-5-stops-working-in-2009/162
http//www.zdnet.com/blog/storage/why-raid-6-stops-working-in-2019/805

There is nothing anyone can do, the more the density of disk (and thus their capacity) is increased the more likely it is that a hard error will happen (and disks manufactured in latest few years have not - generally speaking - showed any sensible bettering in the error rate, and even if they did, it was an order of magnitude smaller than the annual or so doubling of the capacity of hard disks within a "same" form factor).

Additionally (to worsen matters) the whole hard disk industry is far from being "transparent", set apart the reknown Seagate 7200.11 and 7200.12 rate of failure issues, the WD "green" has also shown some preoccupying issues, and right now AFAIK there is not a brand/model that can be called "more reliable" than another one, not even "enterprise" models have shown a substantial increase in reliability.

Among filesytems, maybe I am a bit "partial" to it, but NTFS has been over the years the filesystem I find - if not more "reliable" - at least the one that (if defragmented/checked regularly) the one that provided more successful recoveries, certainly not any (in my personal experience) of the EXTx family, cannot really say about the HFS+, I have no real (or not enough) experience with it to comment on it.

AFAIK I can confirm that more or less all the low cost (hardware) NAS makers (and similar boxes USB connected) use a mostly undocumented firmware (usually Linux based) and often peculiar settings for the RAID array or JBOD, and it is often difficult, unless you have a spare identical unit to analyze, to get head or tails of the actual setup.

It's a mess (.

jaclaz

[1] Don't forget that with today's large capacity hard disks, rebuilding a RAID array takes a looong time.

 
Posted : 11/11/2014 11:03 pm
(@mscotgrove)
Posts: 938
Prominent Member
 

I read today a comment - If data is not in three different places, then it will be lost'. A bit extreme, but actually can be true.

A RAID could well be one of those places.

Another place should be offsite.

Backups should be automatic

Subject to security, data volume etc, Cloud should be considered as one of the three places.

I agree with Jaclaz that NTFS should be considered as there are many good recovery tools

 
Posted : 13/11/2014 12:00 am
(@zul22)
Posts: 53
Trusted Member
Topic starter
 

I totally agree with you jaclaz and thank you for the interesting links.

I see RAID-1 as some kind of very temporary "backup", useful for the recently saved files, but in no case a true backup stored in another place.

RAID-6 appears me a good too. It costs more but should offer high reliability.
This mean however higher cost data recovery if a problem occurs.

I agree that RAID advantage is to reduce down time and not to secure data for the long term. It's easy to figure out what can happen if for instance there is some fire and the fire lances spit water to your RAID storage, and make it fall from the table…

In my opinion, it's interesting to use small drives and clone them on a regular basis. I also suggest archiving on several drives those files that are no more useful for the works in progress.
One problem however with cloning is that many people don't have the competencies, the time and the discipline for this.

Using several small drives instead of one large drive lowers the risk to loose all data and if one drive fails and let work with other files while the data recovery is being done.

I'm always trying to tell my customers to not buy drives over 1TB, as even as even 2TB drives can be boring for data recovery. Some softwares require disk images, and the image of a 2TB drive is itself above 2TB. This mean you require quite expensive drive to store it, and issues with 32-bit OS.

Some self-employed customer in the graphic arts industry recently told me that he needs a 4 TB or 6 TB storage. This appears to me non-sense. I believe he should archive 80% of his files twice on cheap drives and store them in two different places.
Hence, he could invest his money on small capacity drives of better quality for the daily work.

 
Posted : 13/11/2014 3:54 pm
jaclaz
(@jaclaz)
Posts: 5133
Illustrious Member
 

I'm always trying to tell my customers to not buy drives over 1TB, …

Which is good. )

Personally I am even more cautious and (when I am asked about it) I suggest 512 Gb or smaller.

Once you have excluded (within the "small business" realm) some "file intensive" activities *like*

  • Professional graphical designing/heavy photo editing
  • Architects/Engineers doing "heavy" 3d rendering
  • Video producing/editing

The "normal" files produced in a small office should amount to a bunch of gigabytes per year, if a minimum of attention is used.

As an anecdotal report, JFYI, I however received a 15 Mb Word letter (the guy/gal which made the template with the firm name/address used a full scale TIFF file embedded in the .docx file), and since I was a consultant for the company I later found out how tens of thousands of similar letters were created and dutifully saved individually 😯 .

The graphical fields do actually need huge amounts of data, a RAW image from a professional camera (let's say a Hasselblad digital back) is around 80 Mb if I recall correctly and it is not unusual to shoot 200 or 300 shots in a photo session (plus of course the various photo editing with Photoshop and the like), so the request for an online storage of 4-6 Tb in itself may be not as absurd as it may seem (considering that a "normal" NTFS filesystem is likely to start "choking" if filled more than 80%), the point that people (still) fail to understand is that this amount of "online" storage *needs* to be backed up regularly AND at least twice (and that this has a cost, both in money for the hardware and in time to perform the backups).

The part in which *somehow* the industry has failed is, besides - as you pointed out - the lack of "simple" and "foolproof" and "automated" backup tools, is the "different" speed at which things evolved (magnetic vs. optical storage).

I like to repeat how there was just a short period of time (around - if I recall correctly - 1995/96) when we had 500 Mb (or so) disks and 650 Mb (and cheap enough) cd's (which over the years resulted more reliable than waht initially thought).
It was perfect, once a week or once a month one would simply burn a 11 backup on cd, actually starting the creation when leaving the office and getting the cd the morning after (soon later disks jumped up to 2.1 Gb and I used to partition them so that they had three slightly smaller than 650 Mb partitions, one of which was "data only", handy for this kind of primitive backup).

Nowadays you would need to suggest to your customer to get (example) one of these units
https://pro.sony.com/bbsc/ssr/cat-datastorage/cat-opticaldiscarchive/product-ODSD77U/
which at US$ 8,600 apiece and with a cost of around 160 bucks for a 1.5 Tb cartridge would be difficult to call "cheap".

With a "street price" for a 1 Tb 3.5" SATA disk around 100 bucks or below, your suggestion of using any number of "cheap" drives makes a lot of sense.
Optical backup for 6 Tb (twice) 2*4*160+8600= 9,880 US$
Magnetic backup for 6 Tb (thrice, you never know) 3*6*100=1,800 US$
Even if you add to it the cost of (say) 6 USB/eSata hard disk docking stations, let's say 6*60=360 US$ you are still lower that 1/4th of the cost.
There is simply no race.

RDX (which are nothing but "plain enough" hard disks inside a cartridge) may currently be the best "compromise" between cost and practical use by a non-advanced users (ruggedness/easyness), a dock should be around 120 US$ and the same would be more or less the cost for a 1 Tb cartridge.

jaclaz

 
Posted : 13/11/2014 10:47 pm
jhup
 jhup
(@jhup)
Posts: 1442
Noble Member
 

RAID 10 in a rack-mount NAS with ext4, JFS, ZFS or XFS for the data areas.

There are some very inexpensive, yet fully functional solutions out there.

 
Posted : 13/11/2014 11:47 pm
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