Improving mod_proxy : Example of an "home made" balancer: Mod_cluster

* Summary: When using Mod_proxy + Mod_proxy_balancer Apache httpd only 2 balancer modes and reduced management support is possible. Anyway it is possible to write custom balancers to support different type of clusters. A Complete example of a balancer to front-end a dynamic cluster of Tomcat's will presented.Mod_proxy allows to * Abstract: The goal of the presentation is to demonstrate how easy it is to improve mod_proxy interaction with a cluster of Tomcats. There are different session replications mode in clusters. Full replication, Buddy replication, passive nodes for High Availability. Load balancing and failure recovery should be based on a dynamic view of the cluster not on a static description in a configuration file. Recent improvements in Mod_proxy allows the standard Mod_proxy to front-end a cluster of servers but actual ASF mod_proxy_balancer offers only 3 balancer modes (byrequest, bytraffic and bybusyness) and reduced managing support (via mod_status). What is needed to have a completely dynamic cluster: On Tomcat side a Listener to collect and transmit node informations to the balancer module and on Httpd side a balancer module able to use those informations to route incoming requests according to different loadbalancing and failure recovery policies. How it is done: A quick overview of the Tomcat listener of the example and an overview of the balancer module. Explanation the features of mod_proxy that are available to write a balancer. The mod_cluster solution: Protocol, Logic and Tomcat integration. * Expertise level: technical, intermediate * Format and duration: general presentation