rsync seems to overwhelm a failing hard disk

[Chris Dennis]

Hello rsync people

Today I was recovering data from a beginning-to-fail external USB hard disk.

I started with my usual 'rsync -av --ignore-errors <source> <dest>', and 
that was fine until it got to the first I/O errors.  It paused but 
continued after the first couple of errors, but then the disk started 
buzzing and rsync gave error messages for every file (I'm afraid I 
didn't note the exact text of the messages).  After that, every run of 
rsync (trying to --exclude the faulty files and folders) started the 
disk buzzing again, and rsync couldn't copy anything.

The curious thing was that after replugging the disk, I was able to 
manually drag-and-drop a lot more files from the disk via the Debian 
desktop.  Trying rsync again quickly caused the buzzing problem again.

In other words, a simple file copy was able to read the disk when rsync 
gave errors.  Is that to be expected?  Is there a way to make rsync more 
gentle on a fragile disk?

cheers

Chris
-- 
Chris Dennis                                  cgdennis at btinternet.com
Fordingbridge, Hampshire, UK