>>> >>> # just show what is going to change >>> ./changeuuid.py pretend /dev/sdb /tmp/temp/ >>> >>> # actually change >>> ./changeuuid.py change /dev/sdb /tmp/temp/ >>> It's best to first run the 'pretend' command and review the changes before actually writing the changes using 'change'. The reason behind this is that once the UUIDs have been changed in fstab and not on the partitions, there is just one way to recover-> manually. I really appreciate the time you are taking for testing various things. Can you please post the output of the 'pretend' command and the 'change' command? Regards Mandar Joshi