Clonezilla is a free and open source partition and disk imaging/cloning program similar to Acronis True Image®. It saves and restores only used blocks on the hard drive. The file systems supported by Clonezilla are:
(1) ext2, ext3, ext4, reiserfs, reiser4, xfs, jfs, btrfs and  f2fs of GNU/Linux
(2) FAT, NTFS of MS Windows
(3) HFS+ of Mac OS
(4) UFS2 of BSD
(5) VMFS3 and VMFS5 of VMware ESX
(6) Minix of Minix
Therefore you can image or clone GNU/Linux, MS windows, Intel-based Mac OS, FreeBSD/NetBSD/OpenBSD, VMware ESX, ChromiumOS/ChromeOS and Minix. LVM2 and hardware RAID device is supported, too. Two types of Clonezilla are available, Clonezilla live and Clonezilla SE (Server Edition). Clonezilla live is suitable for single machine backup usage, and Clonezilla SE is for massive deployment. Clonezilla is not only for a newbie system administrator, but also for a veteran.

For more info, please visit http://clonezilla.org.