Dealing with Data Degradation or Bit Rots

If you have set up a NAS or alike, such as a FreeNAS system, you know that the system periodically "scrubs" the disks. The disk scrubs are to to wipe clean the disks, instead, they are to prevent bit rots, a slow degradation of data store on storage devices, e.g., a magnetic disk's gradual loosing its magnetic charge.

If you don't have a NAS that does it for you, how do you reduce the chance of loosing the data due to bit rots (or data degradation), in particular, you have lots of important data on external hard drives? There are a number of tools that can help us if you don't wish to take the task into your own hand to program one. This post bookmarks three such tools,

1. CSHATAG
2. ExactFile
3. DiskFresh 

A combination of application number 3 and one of applications number 1 and 2 in the above can give us a piece of mind, i.e., to detect bit rots and to prevent bit rots.