Digital Asset Management
Backing Up Your Archive: How Safe Is Safe?
There is a saying among IT-geeks that a backup is not a backup until there
are at least two copies, one of which is off-site. I use two kinds of backup
media for archive files: a set of hard drives stored at a remote location,
and a set of DVDs locked up here at the studio. I consider the off-site hard
drives to be the primary backup. (I know several photographers who find
DVD burning to be too time-consuming, and choose instead to back up to
multiple hard drives.)
Understanding Threats to Your Archives Well-Being
Just as the new capabilities of digital media bring new solutions, the vul-
nerabilities of digital media bring a whole new set of challenges to the
serious photographer. It’s up to photographers to determine for themselves
how much risk they can tolerate, and to balance that against the cost of
Backing Up Your Archive
Figure 4-19. The big safe safe.
Safe, Storage, Security, Vault
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Chapter 4, Creating the Digital Archive, Part 2: Hardware Configurations
redundancy. Let’s take a look at some of the dangers to your archive’s well-
being, and some of the solutions.
Device failure
Device failure encompasses the entire range of hardware malfunctions that
can befall your storage media. For hard-drive-based systems, this includes
failure of the internal components themselves, such as the read heads or the
data platters. It can also include failure of the drive controller (the circuit
board on the bottom of the hard drive). For any of these problems, your only
real recourse, should you need to get the data off the drive, is to send it to
an expensive data-recovery service.
For FireWire and USB external drives, you can also have failures of the
power supply, the controller board in the case, and the cables. However, you
may be able to fix these problems yourself by changing the cables, putting
the drive into another enclosure, or getting a different power supply.
Device failure for CDs, DVDs, and digital tape means the loss of readability
of the media. This can be caused by breakage, damage from scratches or
excessive heat, or from the media simply degenerating over time. You can
sometimes repair scratches on CDs and DVDs by treating the surface with
a scratch-repairing compound, available at music or computer stores. If the
foil itself (the reflective stuff inside the plastic of a CD or DVD) is damaged,
though, the disc is probably a total loss.
The life expectancy of all digital media is essentially unknown, and even
media “expectedto last for many years can be subject to sudden failure.
The solution that offers the most protection against device failure is to use
multiple media formats, to keep redundant copies, and to check the integ-
rity of your backups periodically.
Viruses are destructive programs that propagate from computer to com-
puter and can wipe out all data stored on rewritable media such as a hard
drives. Because we depend on computers so heavily, it’s important to have
good virus-protection software, and to update the virus definitions regu-
larly. (Viruses are much more common on PCs than on Macs, but Macs do
occasionally get hit.)
If you ever experience unexplained data loss (the drive is inexplicably
empty, can’t be read, etc.), it’s very important to ascertain that a virus is not
the cause, before you open your backup copies and try to restore the data. If
you open your backup on an infected machine, you may destroy it too.
Using write-once media such as CDs or DVDs can help protect against
viruses more thoroughly than hard drive backups alone, because viruses
cant infect your data once it has been burned.
Backing Up Your Archive
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