220.127.116.11. About Clustered Instances
A clustered instance is an Amazon EC2 instance running JBoss Enterprise Application Platform 6 with clustering enabled. Another instance running Apache HTTPD will be acting as the proxy for the instances in the cluster.
The JBoss Enterprise Application Platform 6 AMIs include two configuration files for use in clustered instances,
standalone-mod_cluster-ec2-ha.xml. Each of these configuration files provides clustering without the use of multicast because Amazon EC2 does not support multicast. This is done by using TCP unicast for cluster communications and S3_PING as the discovery protocol. The
standalone-mod_cluster-ec2-ha.xml configuration also provides easy registration with mod_cluster proxies.