These detractors have typically referred to outdated reliability models that have proven to be invalid when applied to tape library technology. Thus, the real world average failure rate for a tape library system is lower than for a combination of single drives. That assessment of library technology runs counter to the conventional wisdom of design which proclaims as more parts are added to a system, the more likely it is to fail, with all other factors being equal. However, all things are not equal and, as noted by Strategic Research, this model for reliability does not apply to library technology. A multiple-module installation is highly insulated against a catastrophic failure by having redundant components.
Monolithic designs provide no similar insurance against component failure.
As demonstrated by the Strategic Research findings, data backup is the largest piece of the data management pie, and an area where automating the process with a tape library can pay immediate dividends. Automated media management ensures proper tape rotation and multiple generations of backup, preventing possible disaster if a tape is damaged. User can restore their own data if permitted, without intervention by a network administrator. The advantages of an automated tape library are even more pronounced in a dual-drive configuration. There are four key points that make multiple drives almost mandatory for today's network storage environments.