Hard Drives as archive storage?

[TFMF]

Recently, I have been copying a lot of old data (Seasons of shows, etc) on to old hard drives I have. They are only small, 40GB max, and have a few years on them, but i was recently told that this is 'risky', because they can easily fail, and it would be safer to burn to DVDs.

 

Apparently, DVDs would last 10-100 years, and Hard Drives would last about 2-5 years. Is this really true? The hard drives are only in use when I copy stuff over, and after that, they are stored away until I need them again.

 

Is this still dangerous? Should I copy everything to DVD?

[TetsuoShima]

It's hard to tell, I can pretty much guarantee you, that not just any run of the mill writable dvd will last 100 years, if you buy el-cheapo stuff and you're unlucky, they could fail within a couple of years, then again, if you're lucky, they could last 20 years, quality control on cheap writable dvd's is low. There are high quality writable dvd's available that should last over 50 years, but they are very expensive, £2/dvd excluding taxes. Then there are the 'brand' writable dvd's (verbatim/taiyo yuden/...), they are in between the two extremes, they aren't super long lasting like the archival grade discs, but they have better quality control, less chance of extremely bad discs making it out into the distribution channel.

 

Then the hard disks... Most hard disks (that will fail) fail within the first year, between 2-3 years, the chance of a hard disk failing is the lowest in its average lifetime, between 3-5 year the chance of the hard disk failing is a bit higher, but still acceptably low, past 5 years, the chance of the hard disk failing rises quite rapidly for each added year. Those are average numbers, each hard drive is different individually, so it's perfectly possible you have a 15 year old hard disk that still spins like a charm, but the chance on that is very low.

 

The problem with hard disks is, when they fail, they usually fail very fast, within a matter of days since you first noticed a problem or even totally out of the blue without warning. And when it fails, it's not easy to get your data back, the older the drive, the harder to find suitable 'spare parts' to repair it (if possible). Sending it to a specialised firm is not affordable by most mortals who've lost their picture collection (easily goes up into the £100's or even £1000's depending on the situation). dvd's also fail without warning, but very often it is quite easily possible for ordinary consumers (with some help or some tech savvy-ness), to get back most of the data on the dvd.

 

If you want to use hard disks as backup storage, you should at the very least run the disks in raid-1 or make a backup of everything on 2 seperate hard disks, but even that is no guarantee, it just increases your odds.

 

There are professional backup storage solutions available that are developed specifically for this purpose and 'are said' to last 100+ years 'easily', they again are not intended for home use (though you can use them for that if you're very wealthy) and are very expensive (£4000+ for just the interface device).

[bones2097]

you should be saving things on dvd, as they aren't effected by magnets... any who i would most likely think that in a few years time blu-ray discs will be the 'in' thing i you'd most likely have to re bacup your stuff!!!

 

go for brand named stuff, like TDK they should be good, but will assume a good life of maybe 5 yrs, after that time i'd most likely re-bacup... i can't say yet since i've only had a dvd writer for about 3 yrs now... but i have very ancient cd, that work fine.

 

though i do keep them in a dark an not too hot place.. (in my wardrobe! ::) )

[Ulysses]

Id personally back up on the HD and on a dvd...

[shadowlink]

any who i would most likely think that in a few years time blu-ray discs will be the 'in' thing

 

Actually right now it looks like HD-DVDhas a better shot at winning the HD format war. According to the latest statistics on Amazon, HD-DVD is absolutely crushing Blu-ray. Out of the top 20, "most popular items in DVD Players and Recorders," HD-DVD occupies 4 different slots, including the #1 slot. On the Blu-Ray side things are not looking so good with only 1 slot and it sits at #20. http://www.amazon.com/gp/bestsellers/electronics/172514/ref=pd_ts_e_nav/103-7398169-0155820

[TetsuoShima]

In a few years I'll be getting me a holodisk backup instead, much safer faster and bigger. :)

[slug]

The most fool proof method is to reduce the data to binary, then carve it into a sizeable rock, bury it underground, alongside instructions about how to build a computer and a pictoral based guide to understanding English for when the various insect based species that survive the downfall of mankind become sentient.

 

Failing that just make sure that you are using Seagate  drives rather than Maxtor or Hitachi Deskstar or pretty much anything else. I would still generally feel safer with optical media. I've had two hard drives leave me in the middle of the night with so many of my prized possessions, not even attempting to split them fairly. It leaves one slightly bitter.

[Hilander72]

Storing on HD's always risky, like TS pointed out, but I really depends on how "valuable" the data is.

 

Personally I prefer to store on DVD's (cheap and fairly quick), but I'm sure that some of them will fail in time (already have for a few commercial DVD's I bought years ago and I don't think my copies will fare any better).

 

Then there's always the Internet... Just upload the data in a torrent and it'll be stored forever somewhere. ;)

[MacPicard]

well if you are damn rich just buy lots of flash media and store everything on that it wont fail for quite a while.  Or if you are not rich use tape drives to back up stuff to it isnt as good as optical but better then HDD's.  The Rev drives work rather well and it is made by Iomega i have one i like it alot just get a 4 pack of 40gb rev drives and good to go. One of the better products that i like from iomega

 

-Picard

[TFMF]

Then there's always the Internet... Just upload the data in a torrent and it'll be stored forever somewhere.

 

The reason I want to back it up is because I just spent ages downloading it. We don't all have your kind of connection! :p

[Rara Avis]

I backup all my DVDs even though I've never had a HD fail on me (yet). I own 10 HDs and some of them are over 5 years old and still going strong. They run from 540MB to 120GB.

 

If they go bad maybe I'll do this to them -

[TFMF]

In a few years I'll be getting me a holodisk backup instead, much safer faster and bigger. :)

 

But will you ever actually install it? :P

 

Well, I suppose I should start burning stuff to DVD again. Does seem safer in the long run... :thinking:

[Chiggy]

I know a little about back up mediums. Flash memory.........not an option once the back up device fails there is no way the data can be recovered, not even if you were Bill Gates best buddy. DVD's, the data is stored as a chemical, this chemical will degrade over time although I am lead to believe if you keep your DVDs in sensible conditions and away from direct sunlight they will live a long and happy life. HD's........my personal favourite since the data can always be recovered if you have a failure, maybe not by you but by one of the many companies out there who specialise in this field. I`m a magnetic medium fan myself although the only disadvantage of HD's I can think of is that they cannot survive many knocks like Flash and DVD's.

 

Want to know what I would do?...............back up the same date to HD and DVD.

[Tigerplayer]

my recommendation would be to store the data on a brand new flash. Flash is the most stable medium that I can think of, especially if it's brand new (or has been erased on less than about 1000 times.)

 

Flash cards (and pens, disks etc.) get less reliable with use and time, especially because of the rather forceful method used when deleting stuff. If you use a flash card or pen, make sure to take good care of the interface. always keep the parts made of metal away from dust and sharp things.

 

Harddisks are also good, at least if you don't use one that is close to death, however, they are pretty fragile... any drop from more than 10-20cm from a surface can potentially destroy it, along with the data. ALso, you need to keep it away from any kind of magnetic source.

 

DVD+/- R(W)s have a max lifetime of about 5-10 years no matter what the manufacturer says. In the equation you have to include normal use, dust, scratches (inevitable) and storage conditions... by the way... there's no way to tell for sure that a DVD can survive for 100, 500 or 1000 years.

 

 

[bones2097]

i suppose theres always raid ....

[TFMF]

I've never actually understood 'raid'. Is that safer?

[TetsuoShima]

Raid: redundant array of inexpensive disks.

 

It combines the hard disks into 1 logical disk (which can still have multiple partitions).

 

There are a lot of different kinds of raid, some more usefull than others. Raid offers some protection, but it not a viable sole backup means.

 

raid-0 (which isn't really raid, as it isn't redundant), combines 2 or more disks into 1 volume, storing different clusters of the same file on multiple disks, thus enhancing speed, if you lose one disk, you lose everything on both disks. data recovery of raid-0 is extremely expensive!

 

raid-1, the simples form of raid, works only in even numbers, usually 2 (or else you have to combine raid versions to use more than 2 disks on raid-1), it simply takes double copies of all files, one on each disk, in essence the disks are clones of each other, even thouh they aren't really clones as the raid info on the disk itself is different.

 

raid-2, forget about it

raid-3, sometimes used in old high end stuff, forget about it anyway

raid-4, forget about it

 

raid-5, uses parity to have redundancy, writes the parity blocks equally divided over all disks involved, in such a way that 1 entire disk can be lost and all data is still retrievable by combining known blocks and complementary parity data.

 

raid-6, similar to raid-5 except with double parity blocks, so 2 entire disks can fail

 

Raid levels are also often combined, creating names such as, raid 01 (or raid 0+1, it's the same), raid 10, raid 50, .... This simply makes 2 arrays of for example raid 1 and puts those two into a raid 0 array, somewhat combining the benefits and disadvantages of both.

 

Remember that the parity in raid5 and6 has to be calculated, so if you want a fast raid5 array, you need a very good dedicated raid card (they usually cost over £300), which in turn will have a dedicated processor and ram, you can use host based solution, but they are significantly slower, especially when 1 disk fails. raid solutions without parity, aren't dependant on processor power.

 

For most home users, all they'll ever probably use will be raid0 (for the impatient who couldn't care less about their data) and raid1 for the anally obsessed data integrity lovers.

 

In reality raid was developed to insure uptime of servers at a lower cost compared to making super reliable disks, as primary backup they are unsuitable.

 

A different kind of combining hard disks, called JBOD, is sometimes also classified as raid, though it is even less raid than raid-0, jbod stands for, just a bunch of disks, meaning, they combine all the disks into 1 single logical volume with no redundancy, file 1 could be completely on disk 1 and file 2 completely on disk 2, ...

 

This is just a very tiny intro, in my own words, possibly not 100% accurate, but overall it gives you some indication. If you want more knowledge on raid than you can remember, use google (no joke, good info comes up). :p

[bones2097]

Thanks for confusing the boy! ;)

[TetsuoShima]

He's doing computing, he should know this, sooner or later... :P

[Amnot Borg]

as explained at http://www.webopedia.com/TERM/R/RAID.html

 

Redundant Array of Independent (or Inexpensive) Disks, a category of disk drives that employ two or more drives in combination for fault tolerance and performance. RAID disk drives are used frequently on servers but aren't generally necessary for personal computers.

 

There are number of different RAID levels:

# Level 0 -- Striped Disk Array without Fault Tolerance: Provides data striping (spreading out blocks of each file across multiple disk drives) but no redundancy. This improves performance but does not deliver fault tolerance. If one drive fails then all data in the array is lost.

# Level 1 -- Mirroring and Duplexing: Provides disk mirroring. Level 1 provides twice the read transaction rate of single disks and the same write transaction rate as single disks.

# Level 2 -- Error-Correcting Coding: Not a typical implementation and rarely used, Level 2 stripes data at the bit level rather than the block level.

# Level 3 -- Bit-Interleaved Parity: Provides byte-level striping with a dedicated parity disk. Level 3, which cannot service simultaneous multiple requests, also is rarely used.

# Level 4 -- Dedicated Parity Drive: A commonly used implementation of RAID, Level 4 provides block-level striping (like Level 0) with a parity disk. If a data disk fails, the parity data is used to create a replacement disk. A disadvantage to Level 4 is that the parity disk can create write bottlenecks.

# Level 5 -- Block Interleaved Distributed Parity: Provides data striping at the byte level and also stripe error correction information. This results in excellent performance and good fault tolerance. Level 5 is one of the most popular implementations of RAID.

# Level 6 -- Independent Data Disks with Double Parity: Provides block-level striping with parity data distributed across all disks.

# Level 0+1 – A Mirror of Stripes: Not one of the original RAID levels, two RAID 0 stripes are created, and a RAID 1 mirror is created over them. Used for both replicating and sharing data among disks.

# Level 10 – A Stripe of Mirrors: Not one of the original RAID levels, multiple RAID 1 mirrors are created, and a RAID 0 stripe is created over these.

# Level 7: A trademark of Storage Computer Corporation that adds caching to Levels 3 or 4.

# RAID S: EMC Corporation's proprietary striped parity RAID system used in its Symmetrix storage systems.