I should have seen it coming when I CDed into my notes/tutorials directory on my data drive and saw the slackware subdirectory being displayed as A FILE!!!

I stupidly rebooted to find that my data hard drive is corrupted and can't be mounted any more. It's a big SATA drive (500GB) so I didn't have anywhere to dd it to.
I've been running fsck -y for the last 48 hours hoping that I'll recover some of the files. I don't know how much longer it'll take.

Now I'd like some recommendations:

1. Which hard drives are most reliable? I'm going to get 2 new ones and set up RAID1. AFAIR, my motherboard lets me do it in BIOS.
2. I've just come across archival grade DVDs. What to look for when buying them? Any recommendations? Which speed of burning is recommended? How to store them?
3. Any other backup medium recommended?

Thank you

Big corporations generally use Seagate Barracuda drives in their mission critical computers. I've seen them last a long time. I've personally had very good experience with Maxtor Atlas drives. Personal experience has also caused me to have a low regard for Western Digital disk drives, particularly their Caviar series.

I'm not a fan of RAID. I used hardware RAID in business for years. It always seemed to create more problems than it solved and it's high maintenance. Software RAID and fake RAID are even more trouble.

RAID on a motherboard will almost certainly be fake RAID. That means that it will have drivers like software RAID. Whether the drivers are proprietary or generic dm-raid Linux drivers you will have to compile them into the initrd and kernel every time you upgrade the kernel. I guarantee that one day you will upgrade the kernel and forget to recompile with the dm-raid drivers. That will be the day that you need your computer to work right away and you will regret using fake or software RAID.

I think RAID is more trouble than it is worth except in very limited circumstances (stock exchange, airline reservations, space station life support).

When I use CDs and DVDs I go for the name brands. My favorite brand is HP. They probably don't make them but whoever does seems to be doing a good job.

I use two external disk drives. I switch between them. They are much more convenient than CD/DVD/tape. In the long run they are inexpensive. They are reliable. I've been using them for years. They are reasonably fast compared to CD/DVD/tape. As far as brands go for external disk drives I start with my favorite brands for system disks (Seagate and Maxtor) and add Iomega and Toshiba. I've used these brands for years. My clients use them. These brands appear to be very reliable.

Thanks

Funny you should say it - that's the drive in question.


I agree probably the most convenient solution would be an external hardrive (ideally two of them). I've got an external drive enclosure that has RAID functions. That would be even better. I wouldn't have to do it on my computer and worry about upgrades.

I've been browsing some online shops and come across 'data cartridges' - what are they? For example:
http://www.ebuyer.com/product/90079

Have they anything to do with data tapes?
Are the cartridges more reliable than HDs?

::

These are DLT tapes. They were a step up from reel to reel tapes. Many large corporations still use them but they are slow and expensive. DLT tape drives can be very expensive. The advantages to using this type of tape are that they are very rugged so they are good for off site storage and they are good for using in robotic libraries.

LOL.

On the website I saw those cartridges there are some cheap ones, but I guess they are not worth it, are they?

Look up the prices on a DLT tape drive. Also, DLT tape drives use SCSI interface.

Too expensive.
It'll be external hard drives then.

I think that you mean to ask '...which brand of hard disk is most reliable...': so, I don't think that you are trying to ask, eg,

• is SATA as reliable as fibre channel?
• would I be better off (from a reliability perspective) having few big disks, rather than many small disks (and, even this, begs the question, did you want "failures per terabyte" or "failures per disk drive" per unit time as your unit of failures...and even that conflates hard failures with, eg, data loss)?
• do different drives within certain manufacturer's ranges have failure rates that are appreciably different from other disks in their range?

...which may be sad, as some of those questions are easier to answer than others.

Here is an article that you ought to read, although it is mostly a summarisation/popularisation of an article here (Disk Failures in the Real World, Schroeder and Gibson).

More on to your point, i did once read a summary of some Russian data which suggested that there was a real difference between brands, but I can't now find that. Hitachi did well, but, bear in mind:

• when they tested (or, incidentally got data as a byproduct of doing something else) they tested what they tested. If, for example, they got one model from one manufacturer that had a particular problem, then that would depress the results for that manufacturer and you would know that, for example, 'Manuf 1 is bad' when a better summary of what went on might be 'most Manuf 1 disks are good, but one Manuf 1 model, which probably isn't available any more, given how long this kind of testing takes to produce data, is one to avoid' which is less informative.
• they tested what they tested, and if, for example, they tested non-raid-specified disks in raid arrays, then it is predictable that their chances of early data loss increase (and this may or may not be a failure, in their methodology)
• it is difficult to know if environmental conditions were equalised (or randomised) across the test population, and maybe the difference is more to do with the environment and usage conditions than the disks themselves

And probably 'enterprise' or 'raid-spec' disk drives are worth the extra, if you care about your data (and, I'm assuming that you do).

There is also this, but google goes out of their way not to mention brands.

1) RAID is not a form of backup. I recommend Samsung and maybe Seagate HDDs (unless they have bad firmware).
2) Taiyo Yuden, burn lowest speed, store in dry conditions away from light.
3) I recommend DVDs.

Thanks for your reply. I'm going to read the links you provided.
I don't know what to ask as I have never dealt with backup solutions.

Ok thanks. I'll also buy a few of those DVDs. Better safe than sorry.

I used to backup to RW DVDs (using dar to create on-disk archives and par2 to create error detection and correction files, odd-numbered days on-site and even numbered off-site) but there were 3 issues:

• Slow to backup (using slow speed for maximum reliability).
• Slowed the whole computer when writing.
• High failure rate of both DVDs and drives (possibly in part caused by hot damp conditions).

I now backup to USB HDDs (using Bacula to create on-disk archives and rsync to replicate Bacula and other key recovery files to USB HDD. 3 HDDs in backup set; one always off-site). This is a much more convenient solution.

Both solutions required a lot of time to develop, configure and test.

One more thing, there a Taiyo Yuden FAQ:
http://club.myce.com/f33/taiyo-yuden-faq-178622/

That's how I found out about these disks. They say they are better than gold foil disks (but are probably about the same quality only cheaper).

P.S.

When I say DVDs I mean DVD-R or DVD+R, NOT anything rewriteable because these media are not designed for backup and are unreliable.

I was still looking for some info that I have seen before. Didn't find what I was looking for, but this might be interesting.

True, very true but backing up two DVDs a day, 7 days a week I couldn't bring myself to create so much waste even though it would probably have worked out cheaper in money.