CentralNotice From Wikipedia, the free encyclopedia Jump to: navigation , search The device mapper is a Linux kernel 's framework for mapping physical block devices onto higher-level virtual block devices . It forms the foundation of LVM2 , software RAIDs , dm-crypt disk encryption, and offers additional features such as file system snapshots . [ 1 ] Device mapper works by passing data from a virtual block device, which is provided by the device mapper itself, to another block device. Data can be also modified in transition, which is performed, for example, in the case of device mapper providing disk encryption or simulation of unreliable behavior. While this article focuses on the Linux kernel's implementation, the device mapper functionality is also available in both NetBSD and DragonFly BSD . [ 2 ] [ 3 ] 1 Usage 2 Features 3 Applications 4 References 5 Ex...