Backing up to a HD is certainly the quickest, and probably cheapest method (in some instances), but has certain major drawbacks:-
- HD's die frequently. If it's fitted in the same box as your server, then you may have to shut down the server to replace it.
- If the backup HD is in the same box as your server HD, then a spike from a faulty power supply could fry both of them.
- An office fire or theft could result in you losing both your main and backup HD's in one go - if you're in this scenario, then you might find your company insurance invalid.
- Tapes are cheap and allow rotation schemes i.e. one tape for each day of the week + another (for example) for alternate Fridays. Why do this? - beacuse if someone accidentally deletes a file or a whole folder, you might not realise it for several days. If you only have a single HD backup, it will already have been overwritten.
- You can archive tapes at regular intervals in a safe, as an additional guard against accidental file deletion going undetected for long periods.
- Tapes are small, light and robust for carrying offsite.
Regards, John Harland