Heartbeat is an older way to implement DRBD between high availability servers.

Setup Quirks

For Cent6:

"drbd84-utils" and "kmod-drbd84" need to be downloaded from here: http://repos.lax-noc.com/elrepo/archive/elrepo/el6/x86_64/RPMS/

Then manually installed with yum shell along with heartbeat:

localinstall ./kmod-drbd84-8.4.11-1.el6_10.elrepo.x86_64.rpm
localinstall ./drbd84-utils-9.5.0-1.el6.elrepo.x86_64.rpm
install heartbeat
run
exit

Basic Usage

 /usr/share/heartbeat/hb_takeover