External hard drives definitely have their place for doing backups. But most people don't realize that inexpensive consumer-grade hard drives fail just as frequently as the hard drives built into their computers. And, if they are right next to your computer, they will typically share its fate in the event of theft, fire, power surges, etc. Now here's another thing to worry about: firmware bugs.

IDG news service reported last month that several models of Seagate's popular Barracuda and DiamondMax external hard drives have faulty firmware that is causing the hard drives to "freeze" under certain conditions. The article that I read refers to this condition as "bricked," a term I hadn't run across before but which is amusingly descriptive of what you can do with a frozen hard drive. Seagate is a great company, so I'm sure they'll fix this problem, but there's only so much you can do when there is a single point of failure.

As I've said in the past, any single hard drive is going to be much more vulnerable to data loss than the RAID arrays that Carbonite uses (which are 36,000,000 times more reliable than a single hard drive because of redundancy). So while external drives are a good and inexpensive way to store big files such as ripped movies or TV shows, I wouldn't consider them safe enough to store my irreplaceable photos or financial records.

— Dave
CEO, Carbonite

The Sunday New York Times had this little story regarding one of the passengers on the US Air flight that crashed into the Hudson River:

“

When US Airways Flight 1549 went into the Hudson River last month, it gave William Wiley, an engineer at Software Associates, a new meaning for the term "computer crash."

Mr. Wiley was on his way home to Johnson, Tenn., from the company's headquarters on Long Island. He had years of work on his laptop, carefully backed up on another laptop — but both were on the plane with him.

Now the two laptops are among approximately 50,000 passenger items that a mortuary company has frozen, in refrigerated trucks, to preserve them until they can be dried, cleaned and returned to their owners."

Good luck getting the data back from a wet and frozen hard drive.

This particular situation is not likely to happen to anyone, but you can imagine innumerable similar circumstances. The more frequent event is that someone breaks into your house or car and steals your computer and the external backup drive sitting next to it. We hear stories like that all the time.

In any event, the US Air story, like the California wildfire stories last Fall, all mount up to a compelling reason to backup online where the data is safe from all these hazards.

— Dave
CEO, Carbonite