SD! and overlapped extents on source drive?

[wrainey]

I made a bootable backup with SD! on an external firewire partition and then ran the Drive Genius verify/repair/rebuild module on the source drive (80Gb 12"pb). All three levels of the module reported overlapped extents (one location, 128 blocks) and 'failed'. Running the same routine on two SD! smart backup copies yielded no similar errors.

Reviewing the Apple page on manually correcting overlapped extents and using fsck to try to detect this problem showed nothing. Definitely not your problem, but this left me wondering if the utility error message was spurious.

It did raise the question whether apparently successful SD! copies (both the immediately prior and an older one) were likely to have two or more corrupted files and whether it was feasible/worthwhile to try to identify them.

Thanks for any advice,

Bill

[dnanian]

Overlapped extents (etc) are caused at a low level, typically because of a serious crash or other event. Any drive present when that kind of thing happens needs to be checked, of course...