Heartbeat and DRBD.

Install all necessary packages ;-)

Example configuration :

Directory /etc/ha.d/

ha.cf:

keepalive 400ms
deadtime 20
warntime 800ms
initdead 240
ucast eth0 192.168.50.2
auto_failback off
node cluster1 cluster2
ping_group network 192.168.50.1
respawn hacluster /usr/lib/heartbeat/ipfail

haresourses:

cluster1 192.168.50.5 drbddisk::filsys0 
	Filesystem::/dev/drbd0::/srv/drbd0::ext3::rw tomcat5

authkeys:

auth 1
1 md5 secret_password

Commando's good to know  :

cl_status rscstatus -- Tell's if you are activ or not.

/usr/lib/heartbeat/hb_standby -- The locale node goes standby and the failover goes active.

/usr/lib/heartbeat/hb_takeover local -- Takes the local node back again.