Disk Mirroring

[Canis Vulpes]

I value my catalogue of photographs and I intend to keep every RAW image shot, unfortunately compressed NEF's at 10MB on average in size use lots of HDD space. I wish to keep two copies on two separate disks but dont want the regular job of coping disk to disk etc.

I thought of disk mirroring but there are million and one products in the market to do this. Does anyone perform disk mirroring?

A second thought was taking an image of a 120GB disk to CD/DVD but I cannot work out the physics in my mind, can this be achieved also?

[Snowyowl]

I recently bought an 80 gb external HD and copied all of my pictures on to it. That really didn't take all that long, now I plan to copy new pictures once a week or so. It seems to be a simple, inexpensive solution to protecting my pictures.

[prostie1200]

Maybe you could look into installing a RAID Array card together with an additional 130gig Hard Drive in your PC. The cost would be about £100 and allows for further Hard Drives to be added at a later date if you require more storage and security.
The RAID system would mean you will never loose any stored data, as everything is mirrored on the next disk, and the next, and so on. This not only mirrors data but all your programs as well.

[Leif]

I use a free program that routinely does a back up to my secondary HDD. I'll check up at home this evening if you wish. It seems to work, and can run in the background at a pre-set time. I plan to buy an external HDD in the next 6 months and will back up to that as it makes sense not to have all image copies stored in the same room in case of fire.

I used to use DVD's for backup but that is such a pain, and they only last a few years anyway.

Leif

[Tannin]

Stephen, on-line backup isn't really backup at all. Sure, it's convenient a the time, but the only risk it protects you against is physical failure of a hard drive. In other words, a mirrored system is protecting you against maybe 5% or at most 10% of the risk.

Don't do it!

What you need is off-line backup - a backup system that protects you against all the possible failures that lead to data loss, not just one relatively rare type of failure.

There are many ways to achieve this. I'll list a few of them, though there are several others.

* External drives (USB, Firewire, or etc.)
* DVD-R (tedious but very effective
* Second, networked system (very convenient, not as safe as the two just mentioned though)
* Drive caddies (cheapest method of all, not too difficult to administer)
* Commercial broadband backup (probably not suitable for your volume of data)
* Tape drives. Can be worth considering, but you need to go for a higher-end unit, so hard drives often work out cheaper.
* And so on

All of the methods I just mentioned, when properly used (which isn't difficult or too tedious) protect you against all risks, not just the low-probability risk of drive failure.

[robski]

I agree with what Tannin has said.

With Raid and mirror they improve your fault tolerance but with "never lose data" never say never. Sh*t happens. Raid and mirror was most useful when cheap disk drives were very unreliable and good disks were very expensive.

Rapidly changing technology causes another problem because media becomes outdated so quickly.

[Tannin]

Your best bet is probably an external drive. Don't fiddle about with small ones, you are going to take more and more pictures as time goes by, so go with a decent-size unit: 200GB as a minimum, 250GB or 300GB is better.

The best way to do this is to buy an external case (a little thing about the size of a largish paperback novel). USB or Firewire, or better yet, a "combo case" that does both. You can buy these at any computer shop. Cost around $50AU, so maybe E20.

Then buy a drive to go into it. Samsung make the most reliable drives on the market at present, if you can't get a Samsung try Hitachi. Avoid Western Digital - they are going through a bad patch right now and their drives tend to be fast but fragile. Buy it from someone you trust not to bash it about in the warehouse - hard drives are very delicate precision devices, and you need to handle them with the same care you'd use for an expensive lens. If that means paying an extra E20, who cares?

Now you have a readily upgradable, readily repairable backup system. All you need to do is at appropriate intervals - once a week or once a month is reasonable - plug the drive in and then drag and drop your new files over onto the external drive. You should be able to start the copy inside 10 seconds - if you can't because it's too fiddly to select files scattered all over the place, then your computer method is disorganised and you need to rethink it. (Computers store so much data that you have to be organised about it - otherwise you are nostril deep in chaos every working day.) Then go away and drink a cup of tea while the data copies. Finally, disconnect the external drive and store it somewhere else!

Leaving the drive plugged in is easy and very tempting: but it's not really a backup at all if you do that. While the drive is plugged in it is vulnernable to power surges, fire, lightning strike, virus attack, user error, computer crashes, and every other risk you can think of. Once you unplug the drive and put it (gently!) somewhere else (such as at your office instead of home, or your brother's house, anywhere in a different building is good) you are very safe indeed.

A better method still is to use two external drives and swap them over alternately. You wind up with a system like this:

* Main drive: all my data
* Backup #1 all my data up to January this year
* Backup #2 all my data up to February this year

At the end of this month, I copy the last couple of month's worth of pictures over to Backup #1, then take it to the office for safekeeping. that gives me:

* Main drive: all my data
* Backup #1 all my data up to March this year
* Backup #2 all my data up to February this year

See the logic? I can lose any single drive and the worst that can happen is that I lose <30 days worth of data. I can lose two drives (big power surge while I was doing my month-end backup let's say) and I still have all my data except for the last 50-offdd days' worth. And this is on a fairly unrealistic and very lazy once-a-month backup schedule. In reality, you'd backup any time you take important pictures - every Sunday night in my case, after I get home from a field trip.

Total cost for a 2-drive system: less than half the price of a Canon 10-22mm lens. I don;t know how that translates into Nikkor terms, but you get the idea.

[Tannin]

PS: I don't actually use that two-drive system I suggested above, I use a needlessly complicated scheme involving multiple external drives and removable IDE caddies and three different computers in two different parts of town and a great big stack of DVDs - largely because I have lots of spare computers lying around and I'm paranoid about data security. For reasons best known to my psychiatrist, I'm pondering buying a completely unnecessary industrial-size tape backup as well. But then I've worked with computers for nearly 30 years and always was fond of overkill.

[Leif]

It's worth pointing out that hard disk crashes are not that rare. Our group at work has had 4 or 5 over the last year or two. I've seen a few at other companies too. And I had a hard disk that required re-formatting once the IT department got hold of it. (A major cause of PC problems for me has been the IT department at work. If they can unplug something, or damage it, they will.)

Also, even if you use a backup system, a fireproof safe is essential if your data is valuable. Every company I have worked for has a policy of doing a daily backup, storing a copy (of the tape) in the fireproof safe, and storing a copy off-site.

Leif

[yelvertoft]

I use the DVD-R option. It takes a couple of blanks to back-up all my personal files. I'm well organised with my directory structures, it's just a quick drag and drop then hit the burn button. Store a copy in the office at work, and a copy in the house.

Very cheap, reliable, and relatively easy.

Duncan