[ale] [OT] Lifespan of Storage Devices

[JD]

On 07/28/2012 12:59 PM, Andrew Wade wrote:
> I am working on archiving some of my pictures/videos/etc. through the years.  
> I'm trying to decide on what storage media would be best for this.
> 
> The main consensus that I've seen on the internet is that the optical disc
> (Dvd-DL) is still going to be the winner.  The problem is that once you get a
> scratch on it, you may not be able to access that 1MB picture.   I've had this
> happen before.
> 
> What do you all think about the following mediums for 10+ year  (and the tech
> format itself still being around - like zip disk, etc.)
> 
> SDHC/XD  Memory Cards  (Fat32)
> Optical Disk (DVD +-R, CD, DVD-DL)
> Hard Drive (Put in storage; has to be in a filesystem that supports >4GB for
> individual files)
> USB Flash Drive(s) (Fat 32)
> 
> and any others.

The total amount and  average file sizes of the data involved matters a bunch.

I don't expect any media to be around 10 yrs from now and there's pretty much
zero chance that anything I put on media of any type today will be alive AND
TRUSTED in 10 yrs.  Do you still trust those SCSI2 or IDE drives from 2002? I don't.

For important data, I need
* 3 copies
* in at least 2 different physical locations over 500 miles apart,
* on at least 2 different media types
* that are all verified periodically to ensure no data rot.  Usually once a year
is enough.

For really critical data, keep a local backup, a remote backup 3 states away and
local optical backup with par2 files to watch for bitrot.  At the first sign of
bitrot on any of the media, I assume they will all fail shortly and switch in
new media. Reburning a fresh optical disk with new par2 files finishes out this
safety net.  There are probably more copies of this critical data around, but I
only maintain 3.  These are backups, not the hot-copy used daily. If I were
backing up DVDs or Bluray media, the original media disks would never be touched
by anyone after the backup copies were made the same day the new media arrived.

The availability of par2 files has saved some important family photos and home
movies about 5 times the last 10 yrs.  dd_rescue (or the other version) is not
enough.

For really, really important data that doesn't eat tons of storage, like the
different KeePassX databases, I store them in at least 6 locations and 4 media
types - flash, hdd, remote hdd, and optical with par2 files.  The optical does
become out of date for a few passwords, but when you have hundreds, that isn't
too important.

Obviously and sensitive critical files are encrypted with long, random, pass
phrases that I don't know.  The same for backups to any portable devices -
truecrypt volumes rock.

For 20+ TB, I'd probably use tape instead of optical or perhaps that total
amount needs to be raised to 50TB? Bluray could be cost effective if the media
costs work out and enough writers and readers were available in the business.
>From a personal use standpoint, I think Bluray is broken, so I don't have any in
the house. Eventually, I might install a few writers should the media become
cost effective and convenient when compared to DVD-DL - it has been really close
on the cost side, but the convenience is still an issue for me. Considering I
purchased 2 DVD-DL writers in 2012, I have doubts bluray will be used anytime
soon here. I'm stubborn that way, sometimes to my own detriment.

We all know that RAID is not a backup, since having 2+ copies of corrupted data
doesn't help anyone with a restore. ;)

I can't wait to read what others are doing for this problem.