Clonezilla, based on DRBL, Partition Image, ntfsclone, and udpcast, allows you to do bare metal backup and recovery. Two types of Clonezilla are available, Clonezilla live and Clonezilla server edition. Clonezilla live is suitable for single machine backup and restore. While Clonezilla server edition is for massive deployment, it can clone many (40 plus!) computers simultaneously. Clonezilla saves and restores only used blocks in the harddisk. This increases the clone efficiency. At the NCHC's Classroom C, Clonezilla server edition was used to clone 41 computers simultaneously. It took only about 10 minutes to clone a 5.6 GBytes system image to all 41 computers via multicasting!