To create a clone of a SQL server from scratch (~pseudocode):

• iptables -A INPUT -p tcp --dport mysql -j REJECT
• Wait for connections to die down
• mysql -e "show master status" and save the output
• mysqladmin shutdown
• umount /path/to/mysqldata
• sync
• lvcreate -s -L 10G -n snapshot /dev/vg/mysqldata
• mount /path/to/mysqldata
• /etc/init.d/mysql restart
• Copy from /dev/vg/mysqldata at your leisure