重點摘要

Apache can be used to load balance Tomcat servers. This setup provides other useful features such as ‘Server affinity’ and safe removal of nodes for scheduled maintenance.

Load balancing is recommended if transparent failover is not required. It is easy to setup load balancing and ‘server affinity’ with Apache.

JMeter can be used to load test the configuration and to test the behaviour in case of a server crash.

The load balancer can become the single point of failure. This can be reduced by using 2 load balancer and using round robin DNS to delegate request to more than one server.
參考資料
http://www.theserverside.com/tt/articles/content/LoadBalancingTomcatApache/article.html