Best method for archiving image files?

[rc53]

I think that several [external] HDDs are the easiest method. I live in two countries, use two physically separated computers, each of which has a single external HDD. And I have a couple of the small USB powered drives, which I use when 'commuting'.

So all my pix are on two computers' main drives, and their external drives, as well as the USB ones. As long as I back up regularly, I feel the chance of loss is small.

But, all HDDs will eventually fail, and a suggested usable lifetime is about 3 years. And anyway, in three years the files from newer cameras will be much bigger, so storage requirements will be that much greater. The price of HDDs seems to be falling as much as their capacity is increasing, so that every 3 years or so, what you get is greater storage for less money. Bit of a chore having to back up, but safe.

[rc53]

If you want to have a bit more time and a bit less money, give some thought to getting an LTO 3 tape drive (800GB Compressed (average), 400GB Uncompressed) - should be good for somewhere in the vicinity of 25,000 images per tape - and tapes are relatively inexpensive.

Back in the days of audio cassettes, there were problems with imprinting if the tapes were't run occasionally -- because the tapes were tightly wound and close together, there was a sort of cross-fertilization, meaning that the music was a bit garbled.

Is this a problem with these tapes.

And, I see you suggest SCSI. Surely this interface is outdated now.

[Colin Southern]

"But thats the point, most people here are not global multinationals where cost is not that important, the combination of cost effectiveness at an everyday scale combined with longevity is the key. "

I agree that it's not the ideal solution for everyone - it's best suited to those who have so much data that they struggling to back it up cost effectively - and safely - with other technologies; Sedali indicated "I think I got myself a full time job with this back up issue" and "no DVD can keep up with the volume of data that is generated every couple of days" - thus it seems like he might have the need for a streaming tape backup solution - hence the reason I brought it up.

I've used HDDs for backup for many clients, on many occasions - but I think it's important that people don't get lulled into a false sense of security with them; I have lost data using them for backup - I backed up a photography drive (mirrored set) using one prior to changing a Motherboard (suspecting that the change would break the RAID set, which it did) - when I restored it I discovered just about every single large file was corrupted (and it was my additional backups of my commercial work that saved the day). I'd had 1 client go to use their external USB HDD one day to find that the drive had failed and I've had restores for 2 clients fall over because of corrupted backup sets. These are failures that can be mitigated against by switching on verify and maintaining multiple backup devices - but I suspect that many people wouldn't know if they had verify turned on or not - would probably write their data to 2 drives (at the most, if that) - never test the system by actually doing full trial restores - and usually don't keep at least one copy of the media in a seperate location (which in itself often presents planning and transport problems that one doesn't suffer from with tapes because it's easier to have a lot more tapes "in the system" than it is to have drives).

All in all the backup plan becomes more one of "good luck" than one of "good management" - with tapes it's still a disipline, but things become simpler - I suggest to my tape drive clients that they use a staged approach where the system is backed up Monday through Thursday to seperate tapes everyday - a seperate Friday tape is used for each possible Friday in a month (which is kept offsite) - and end of month tapes are not cycled for several months (or are permanantly archived). In the event of failure we can go back one day at a time for a week, one week at a time for a month, or back to one of several end of month tapes.

Cheers,

Colin - pbase.com/cjsouthern

[Colin Southern]

Is this a problem with these tapes.

No - they're a far cry from the audio cassettes of yester-year. Their archival rating is 15 to 30 years (without re-writing).

And, I see you suggest SCSI. Surely this interface is outdated now.

No - far from it - it's just not used very often at the personal computer level because of the cost. Still by far the most efficient interface for large multi-user servers - and when you need to move a powerhouse of data in the quickest possible time (which you need to do with tapes to keep them streaming at full speed) (up to 160MB (Mega BYTE) per second with compression on). Biggest issue is that your standard SATA II drives can't keep up (The SATA II interface can, but the mechanics of reading (fragmented) files drags it down (you really need SCSI striped RAID arrays to keep them fully occupied).

Cheers,

Colin - pbase.com/cjsouthern

[Alis]

One things I recently heard against the tapes is that with a for example RAID system, you know there is a problem with one of the disks as soon as it happens and you can fix the problem but with the tape, unless you check it frequently, which is not what usually happens, you will never know about the problem.

[Colin Southern]

One things I recently heard against the tapes is that with a for example RAID system, you know there is a problem with one of the disks as soon as it happens and you can fix the problem but with the tape, unless you check it frequently, which is not what usually happens, you will never know about the problem.

Hi Ali,

With tapes you'd generally have the verify after write option turned on - plus - they write a small amount of redundent info.

RAID isn't used for offline storage - with tape backups you generally get more redundancy than RAID anyway, as the same info is written to multiple tapes on different days - kinda. Different tools for different jobs though.