Fault Tolerance

Establishing Fault Tolerance is the process of making sure that there are several lines of defense against accidental data loss. An example of accidental data loss might be a hard drive failing, or someone deleting a file by mistake. Usually, the first line of defense is having redundant hardware, especially hard drives, so that if one fails, another can take its place without losing data. Tape backup should always be a secondary line of defense (never primary) While today's backup systems are good, they are not fail-safe. Additional measures include having the server attached to an uninterruptible power supply, so that power problems and blackouts do not unnecessarily harm the equipment.