Created attachment 85840 [details]
output of udisksctl dump, note sdb1 and its copy sdg2 have same UUID
I used `dd` to make an exact copy of an NTFS partition to a partition on an external USB hard drive. It worked, but when I attach the USB drive and try to mount the partition copy using KDE's Device Notifier or Dolphin file manager, it confuses the KDE Solid layer in Kubuntu 12.04, 12.10, and 13.04, because the two drives have identical UUIDs. (More details in https://bugs.kde.org/show_bug.cgi?id=303508 .) The fix for KDE is "easy", just change the UUID of the external partition. But there's no way to do this using udisks or udisksctl (or NTFS tools); instead Googling finds others wanting to change UUID, and suggestions like http://art.ubuntuforums.org/showthread.php?t=1240146 which require using `dd` to overwrite magic offsets in the raw partition, which is highly prone to unrecoverable disk-damaging errors.
Someone recommended in my KDE bug that I file a bug against udisks to add the functionality to change the UUID of a drive, so here I am.