Digital BW, The Print

It is most unfortunate but the bottom line is that hard drives have a 100% mortality rate. It is not a question of will it fail; it is only a question of when. Although a hard drive will fail, it will retain the magnetically encoded data indefinitely although this can be very costly to remove from a failed hard drive. CD/DVDs will not hold data indefinitely. CD/DVDs lose data overtime due to oxidation. Depending on the media, burn process, and storage of the media the life expectancy has a huge range of 2-20 years.

On my servers, I use redundant mirrored RAID hard drives. Unfortunately, RAID is of little use if the server is destroyed or stolen so I also use offsite backup. For automated daily backup I use on online service. I also like to have months old copies of the data and every now and then you run into problems with backup services or software failing. For that reason, I also have a networked Terabyte drive that I plug monthly into the network and do a full backup and then take that drive home. That gives me two offsite backups created in different ways so if my entire business burns down I have good odds of recovering most of my data.

Cheers,
Mark
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