Re: 2.4.10 and dd

Jesper Juhl (
Wed, 26 Sep 2001 18:46:22 +0200

Klaus Dittrich wrote:

> I do my backup using dd if=/dev/sda of=/dev/sdb bs=1024k.

ehh, isn't that kind of dangerous???

What if files move around on disk while dd is running? imagine that dd is in the process of copying blocks belonging to a big file "foo",
and now in the middle of this something causes "foo" (or just parts of "foo") to move to a different location - you now have a seriously screwed
copy of "foo" on the new disk...

I'd expect that all sorts of strange corruption of the copy could happen that way. I could be wrong, and maybe someone who knows more about
how the filesystems work can tell if I am, but I know for sure that I would never dare to do backups that way.

Best regards,
Jesper Juhl

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at