Then there were the multi-platter removable disc drives with 20, 35, or 75Mb per drive. Now you could backup much more data in about the same amount of time.

 

When the larger non-removable disc drives became popular around 1980, we started backing up to 1/4" tape. This process was slower, and it was tedious to change tapes as they filled. That technology was popular for over 10 years and eventually replaced with the smaller and more dense 4mm tapes that we have been using ever since. The capacities of these tapes increased, but the amount of data to be backed up increased as well. Backups might take from 30 minutes to several hours, but often would fit on a single tape, so the backup process was typically run unattended at night.

 

But tape drives with their mechanical parts and head that wears have been the weakest link in computer systems for some time. Tapes also have a limited life and need to be replaced on a regular basis.

 

After 35 years of backing up to tape, this technology is being phased out. The small IBM servers, now a part of Lenovo, no longer will offer a 4mm tape drive option.

 

As disc drives increase in capacity and internet speed and reliability improves, most servers will have at least one recent backup copy on disc and the ability to re-create a disc image with the contents of any of the last 30 days or the first day of the last 12 months using cloud based storage.

 

The technology that really enabled this change is the ability to only copy the sections of the disc that have changed and not the entire disc as we have been doing with tape. The backup times are shorter, yet there is still the ability to restore files in about the same time as you could with tape.