Carelessness backups

The third type of backups that we support are Carelessness backups which allow for restoring of individual files that have accidentally be lost or corrupted. The use of snapshots as mentioned earlier provide this for the short term of a day or maybe a week, depending on available storage space. However this is well short of the 12 months that we currently provide.

We provide this long term for backups without excessive space usage by ignoring many classes of files that are expected to be very uninteresting, such as very large file, automatically created files (dot-o files) and other classes. This is not possible with snapshots which are very much an all or nothing approach.

Exactly what scheme we will use when this filesystem goes live is not yet clear, but I suspect a heuristically limited incremental backup scheme similar to our current scheme, but using the high-bandwidth interface that was created for archival backups will meet our needs quite effectively.