[Discussion] Disk Backup to CD (Carl Gehr)

[Bill Nicholls]

Keep in mind that CDs are *not* a robust mechanism for storage. Both 
heat and light will accelerate the aging of the CD.

As my friend Van found out, never leave you CD on a windowsill. He 
picked it up after the afternoon sun had hit it for about two hours and 
it was totally erased.

Unless you have a fireproof safe that limits the inside temp to boiling 
water, the heat from a fire will also destroy non-stamped CDs. All in 
all, they really are only a temporary storage medium.

Alternatives:
1. DVDs - these are harder to erase, but not proof against a lot of 
light or heat.
2. Tape - the traditional backup still has a lot of value. Van tells me 
that good tape drives, often with useable tapes, are available on ebay 
for 5% of original cost, sometimes less. A good tape in a (non-cheap 
2000 degree F, 2 hours)) fireproof safe will survive even a very hot fire.
3. Raid Drives - This is my current mecanism for backup, though I am in 
the process of setting up a cheap DDS4 tape backup system, using Bacula 
(recommended open source). A pair of RAID1 200GB drives is about $125, 
and even a fire is unlikely to destroy the data unless the drives get 
hot enough to warp.

Recommendation:
This is what I am doing. I already have multiple RAID1 drives in 
different systems. I backup core files to two sets of raid drives if 
they are important. For my video files I have a 1T RAID5 that can be 
expanded to 2.5T with three more 500GB drives. I can recommend Hitachi 
for this, though Segate's best are also fine, about the same price. 
Currently high quality 500GB drives go for about $130-140.

In the next month I will be setting up the tapes and buying a $3-400 
fireproof safe.

I know it's not cheap, but have you considered how much it costs to 
recover data from one drive? $300 down, no upper limit and no guarantee. 
Ouch!  Remember, digital photos and other personal stuff cannot be 
replaced and insurance is not much compensation.

BillN