Setup TCP/IP clustering with Linux's heartbeat

1. Download the libnet and heartbeat source code, install it in all the nodes
   Libnet source code (v1.1.2.1)is available @ http://www.packetfactory.net/libnet/
   Heartbeat source code(v2.0.0) is available @ http://www.linux-ha.org/
   The source package will install heartbeat's binaries to /usr/local/lib/heartbeat and the config files to /usr/local/etc/ha.d
   
   
2. Configure heartbeat in all the nodes
   Create the file "ha.cf" in the /usr/local/etc/ha.d folder and type the following content.
   
   debugfile /var/log/ha-debug
   logfile /var/log/ha-log
   node wsn03-99
   node tser-linux-dev1 # List our cluster members
   keepalive 1 # Send one heartbeat each second
   deadtime 3 # Declare nodes dead after 3 seconds
   bcast eth0 # Broadcast heartbeats on eth0 and eth1 interfaces
   ping 192.168.3.253 # Ping our router to monitor ethernet connectivity
   auto_failback no # Don't fail back to paul automatically
   respawn hacluster /usr/local/lib/heartbeat/ipfail # Failover on network failures
   
   node wsn03-99 and node tser-linux-dev1 is the host name of the node that returned by the command "uname -n" ,the line ping 192.168.3.253 is the router address.
   
   Create the file "/usr/local/etc/ha.d/haresources" and type the following content
   
   tser-linux-dev1 192.168.3.150 httpd
   
   tser-linux-dev1 is the preferred host, the IP 192.168.3.150 is the virtual IP address and must not be used by any machine. "httpd" is the script name of the service that needed to be clustered, it must match the file in /etc/init.d or /usr/local/etc/ha.d/resource.d/
   
   Create the file "/usr/local/etc/ha.d/authkeys" and type the following content
   
   auth 1
   1 sha1 key
   
   The "key" is the authorized key generated by some utility, for sake of simpliclity I just put some value. Apply chmod 600 to this file
   Finally, make sure all the nodes has the same set of files and heartbeat is ready to run. To start heartbeat type "network heartbeat start"
   
   
3. Configure Apache for clustering
   In the apache's http.conf file, includes the following directives
   

   Listen {virtual-IP}:port-number
   
   In addition, disable the startup service of apache in the
   /etc/init.d because the heartbeat service will take control of it