Article #1 Data Backup
The important thing about data back up is to have several copies of your precious data. These copies can be made in any format (or media). Every kind of media are capable of failing, leaving you with no data - so don't obsess on which is the best kind, just make multiple copies of cherished files.
I was talking to my father-in-law Joe recently on this topic. He was concentrating on the format of the back up - worrying about where to keep his old data. His idea was that while you were using a file, you kept it on your local hard disk, then as it became older, and less used, you moved it onto some other format. What he wanted to know was - which media was best? (This process of moving older data onto alternative media is in fact Archiving, rather than backup, and archives need backing up as much as current data).
I advised Joe that the format of the backup media is not the main issue - you can use disks (hard disks, DVD, CD etc), flash ram (cards or keys) even floppy disks. The important thing is to have several copies of anything important. Different kinds of media are more convenient, some are smaller (for the amount of data they carry), some are statistically more reliable, but all can fail, and that failure can leave you without (possibly precious) data.
As I said, some media is proven more reliable than others, but in the end, any kind of data store can fail. I recently heard a program on BBC radio where they apologised for not airing part of a previous program they had wanted, but that it had been committed to CD, and that, when retrieved, that CD proved unreadable. I assume that no other copy of the item was made.
So my point then is to make many, several, (at least more than one) copies of important data. This includes current data, on your hard drive, and older information. Make multiple permanent copies (preferably on different media) of important data before wiping it from your hard drive.
Different kinds of media have features which make them more convenient or useful. Recordable optical media (data CDs and DVDs) are useful in that they can be written once only. This means it is impossible (or at least difficult with re-writable disks) to overwrite important backup data accidentally. USB Hard Disks and flash RAM are convenient in that you can quickly and easily create a backup.
So what copies should you make? This depends on how often you change the data on your drive, and how much you're prepared to lose. Losing some data at work may mean re-entering the data (if you still have it), and so may mean several hours work. Schedule a backup based on how much work you're prepared to redo. At home, losing data may mean losing precious photos which cannot be replaced so it’s important to backup whenever you make large changes to the data.
Finally, how to make backups. Here are the tips you need to make backups:
- Remember you're making backups against the day you need that data. Make sure that you label backups well. This is important especially with media you use once - CDs and DVDs - write on them the date you made the copy and the content.
- When you use media that you re-use, e.g. hard disks, never backup over your most recent copy. If the backup process fails, you've lost both your current data, and your backup. Use at least two backup media and alternate between them.
- Use a variety of backup media. If you usually use hard disks, make occasional backups of specific items onto CDs or DVDs.
- Backup frequently - backups can take a while, especially if you have music, pictures and video. The process can usually be left to itself, so do it frequently.
- Backup especially after you have changed your data - so if you've just moved a lot of pictures from your camera, do it then. If you're about to delete a lot of old data, do it then.
Kevin Young - Yorkshire Oak Ltd
You can download this article as a PDF here