Alfresco Clustering

Scenario: 
Alfresco Version: Alfresco Enterprise 3.1
OS: Centos 5.5
Alfresco installation directory: /opt/alfresco
node1 IP:  10.165.22.11
node2 IP:  10.165.22.12

We have two nodes (node1 and node2). We are here going to use alf_data and db of node1 in all cluster nodes
(node1 and node2). alf_data will be shared through nfs and in Database we have allowed access for both the 
nodes to connect.

To configure cluster perform following steps.

On node 1:
Step1 : First share alf_data directory through nfs
open /etc/export file and add following line in it.
/opt/alfresco/alf_data 10.165.22.12(rw,no_root_squash,async)

then restart nfs service.
/etc/init.d/nfs restart

Step2 : Create DB and grant permission for both nodes to connect. Run following queries on mysql.
create database alfresco default character set utf8 collate utf8_bin;
grant all on alfresco.* to 'alfresco'@'localhost' identified by 'alfresco' with grant option;
grant all on alfresco.* to 'alfresco'@'localhost.localdomain' identified by 'alfresco' with grant option;
grant all on alfresco.* to 'alfresco'@'10.165.22.12' identified by 'alfresco' with grant option;
grant all on alfresco.* to 'alfresco'@'10.165.22.11' identified by 'alfresco' with grant option;

Step3 : Now create directory for dir.index and dir.index.backup
mkdir -p /opt/alfresco/alf_data.index
mkdir -p /opt/alfresco/alf_data.index_backup/

Step4 : now edit /opt/alfresco/tomcat/shared/classes/alfresco/extension/custom-repository.properties file and 
change following things.
dir.root=/opt/alfresco/alf_data/
dir.indexes=/opt/alfresco/alf_data.index
dir.indexes.backup=/opt/alfresco/alf_data.index_backup
alfresco.cluster.name=testcluster
index.recovery.mode=AUTO
db.username=alfresco
db.password=alfresco

disable derby connection, putting comments in front of below two lines.
#db.driver=org.apache.derby.jdbc.EmbeddedDriver
#db.url=jdbc:derby:alf_data/derby_data/alfresco;create=true

Enable mysql connection, by removing comments in front of these two lines.
db.driver=org.gjt.mm.mysql.Driver
db.url=jdbc:mysql://10.165.22.11/alfresco

Step4 : Now create ehcache-custom.xml file. Run following command.
cp /opt/alfresco/tomcat/shared/classes/alfresco/extension/ehcache-custom.xml.sample.cluster 
/opt/alfresco/tomcat/shared/classes/alfresco/extension/ehcache-custom.xml

On node2:

Step1 : First mount alf_data directory through below procedure.
Do entry in /etc/fstab file to access shared directory of node1. Save the file and exit.
10.165.22.11:/opt/alfresco/alf_data     /opt/alfresco/alf_data nfs rsize=8192,wsize=8192,timeo=14,intr

Now mount alf_data directory through below command.
mount /opt/alfresco/alf_data

Step2 : Now create directory for dir.index and dir.index.backup
mkdir -p /opt/alfresco/alf_data.index
mkdir -p /opt/alfresco/alf_data.index_backup/

Step3 : Now copy  custom-repository.properties and ehcache-custom.xml files from node 1 and paste in 
/opt/alfresco/tomcat/shared/classes/alfresco/extension/ directory.

Now start the alfresco on both nodes and do testing.