The most important task of any system administrator is backing up the systems they are responsible for.
Not putting the system up or not keeping it running as not backing it up and being able to restore is primary.
A system with no backup cannot be relied upon for any real purpose, because if anything goes wrong your data is gone, and that’s really bad news.
Something always goes wrong eventually, no matters how much you try to avoid it, and without good backups all of your work, and possible your entire business is just plain gone.
A good backup strategy is composed of backup, storage, verification, and restoration.
The backup component covers selection of method and which data to backup (all of it by choice).
Storage covers both what media you back up onto as well as where you keep them (if your building burns down, tapes kept in the server room will be useless).
Verification is a crucial component of a backup strategy, you have to know you have usable data.
Lastly, you need to be able to get the data back to where it can be used.
There are two main strategies for backups: Disaster Recovery and...