Distrubuted Redundant Block Devices

What is DRBD? Well in a nutshell, it's a method of taking to stand alone servers, and creating a block level mirror of data devices on one of them to the other. This allows for complete failure of one system without loss of data or data availability.

Think of a DRBD device as a RAID1 array across two distinct network servers. Here is a illustration from the DRBD website:

DRBD is a core technology ACT USA incorporates in it's data centers. It sits at the center of our high availability virtual server farm, and provides flawless fall-over in the event of hardware failure.

ACT USA offers consulting services to assist other businesses and educational organizations in implementing DRBD.