It doesn't matter what how big or small your organization is; determining the most critical information to be included in backups is step one for DR planning. Regardless of what type of OS and network architecture make up an IT environment, the most critical information to be included in backups will always be your business critical application data.
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, network configuration, assuming you will be restoring over the network and finally, configuration information based on system criticality.
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About the author: Pierre Dorion is a certified business continuity professional for Mainland Information Systems Inc.