The document describes setting up a high availability MySQL cluster with DRBD, Corosync, and Pacemaker on Linux. DRBD is configured in active-passive mode to synchronize data between two nodes. Corosync and Pacemaker provide cluster management and failover capability. MySQL runs in active mode on one node, and the virtual IP and data are failed over to the other passive node if needed for high availability. The steps provided include installing and configuring DRBD, Corosync, Pacemaker, generating authentication keys, and configuring the DRBD resource and cluster.