ditto will clone the booted volume, but you will need to use -X lest it try to copy /dev/* and /Volumes/* which will turn ugly.
I've had several "experts" tell me that they heard an expert somewhere say cloning/backing up a booted volume is a bad idea, but nobody could tell me why or provide anything more than hearsay to back up their words so I am ignoring them
I work for the Department of Redundancy Department
