To clone a faulty or dying drive, run ddrescue twice. First round, copy every block without read error and log the errors to rescue.log.

# ddrescue -f -n /dev/sdX /dev/sdY rescue.log
Second round, copy only the bad blocks and try 3 times to read from the source before giving up.

# ddrescue -d -f -r3 /dev/sdX /dev/sdY rescue.log