DRBD (Distributed Replicated Block Device) is a Linux-based software component that facilitates the replacement of shared storage systems by networked mirroring. DRBD makes it possible to maintain consistency of data among multiple systems in a network. DRBD also ensures high availability (HA) for Linux applications.
DRBD was originally conceived and developed in the late 1990s by Philipp Reisner and Lars Ellenberg. The developers' purpose was to create a Linux security standard that would offer optimal reliability at minimum cost. The software has continuously evolved since that time. The current version of DRBD can be used with all common flavors of Linux for synchronous replication of stored data between a passive system and an active system. Data can be read from and written to both systems simultaneously. DRBD also supports resource-level fencing. DRBD works in conjunction with a cluster management program known as Heartbeat and has been bundled into some distributions of Linux.
DRBD is a registered trademark of LINBIT Information Technologies GmBH, headquartered in Vienna, Austria. The software has been released under the GNU GPL (General Public License) and can be freely distributed and modified within the limitations of the license agreement.