"I'm assuming that MySQL is already set up and running
on your system. The system must use LVM, and the MySQL data
directory (/var/lib/mysql) should have an LVM partition of its own
(althouth that is optional).
"If you have read Back Up (And Restore) LVM Partitions With LVM
Snapshots you know that LVM snapshots require some unused LVM
partition for the snapshot. My test system has a second, currently
unused hard drive /dev/sdb that will be used by mylvmbackup to
create a temporary logical volume for the backup."