Advanced WebLogic Cluster
Use this architecture only if you cannot use the Generic Webserver Cluster discussed in a following section. This architecture improves the Simple WebLogic cluster by removing the single point of failure of the WebLogic proxy server. High Availability is achieved by using a load balancer.
For this setup:
􀂃 Use WebLogic proxy serving HttpClusterServlet web application.
􀂃 Use Loadbalancer with loadbalancer-cookie based session sticky for HTTP and SSL based
session sticky for HTTPS
􀂃 All instances must use the same HTTP/HTTPS port e.g. 5010/5011 in the example. This requires
IP Aliasing if the host does not have dedicated network interfaces for each webserver instance
􀂃 One proxy server load balances across all the WebLogic instances on that host only, so you will
use a different multicast address for each host in the cluster
􀂃 The proxy will only pass all calls to the webserver instances.
􀂃 WebLogic proxy server and WebLogic servers providing PIA are run as WebLogic Managed
Servers
Advantages:
􀂃 Good Scalability
􀂃 Good fault tolerance
􀂃 Good flexibility of adding/removing servers dynamically
􀂃 Works with non identical webhosts
Disadvantages:
􀂃 Proxy adds an additional layer
􀂃 WebLogic proxy requires IP Aliasing for running multiple instances
􀂃 Reasonably complex to setup
