One of the latest buzzword phrases in the backup software business is storage management. Just as some people think the word “Internet” was invented within the last few years, many think that storage management is a new concept. It actually goes way back to the mainframe days when 3480 tapes were much less expensive than DASD disks. It became necessary to move important, yet unused, data off the expensive disks and onto less expensive 3480 media. (This is one way of managing the available storage, thus the term storage management.) SCSI disks were a lot cheaper, so Unix environments just bought more disks as they needed more storage space. Unfortunately, this “disk is cheap” mentality has led users to create far more and far bigger files than ever before. Within the last few years, though, IS managers have started to become very frustrated with the amount of money they are spending on disk. They believe that there are a number of files that could be moved from disk to a slower storage medium without anyone noticing. This belief has given rise to a demand for storage management in the Unix arena. Just what is storage management, though?
This section examines the two principal storage management concepts that relate to backups:
Hierarchical storage management
The first principal storage management concept we will address is archiving. In most distributed circles, archiving typically has meant backups that are retained for a long time. ...