Beyond that, any information (or data) that cannot easily be recreated should be included in the backups. For example, many question the practice of backing up operating system binaries since an OS can be reinstalled just as easily as it can be restored. Besides, you typically need an OS before you can restore anything (including the OS itself). However, any hardware, software or network configuration information should be backed up in some fashion if recreating it requires a lot of time and effort.
Arguably, the order of priority for information backup after business critical data would be: The backup server configuration information (including the media catalog) since this will likely be the first thing you would restore following a disaster. Then comes network configuration, assuming you will be restoring over the network and last, configuration information based on system criticality.
This was first published in February 2005