I am using JBoss 5.1.0.GA on Red Hat Linux 4. We have only webservices deployed on this application server as .war files (servlets only, no stateful applications present). As a part of our architecture change for improving scalability, we are planning to have multiple JBoss servers running (may or may not be on different IP’s and machines) and have a load balancer in front of them to distribute the load. Some of those I know recommended Oracle WebCache for load balancing.
When I started using it, I am able to load balance between the JBoss home page, i.e., requests for viewing the http://loadbalancer-hostname:8080/ brings up the actual JBoss home pages for both the servers in a round robin fashion.
I am trying to simulate external load on the webservices and started using soapUI plugin for NetBeans to do this. When I import the WSDL using the loadbalancer-hostname, it is imported fine, but when I load test it, the requests always go to the same server. My assumption is : When soapUI imported the WSDL, the actual WSDL file would have its <soap:address location="http://actual-server:8080/...?wsdl">. May be this is causing soapUI to always hit the same server.
My question is does Oracle WebCache perform load balancing for webservices as well ?
Yes it can.
A web service URL is like any other URL to the load balancer.
What’s most likely happening in your case is the DNS look up is getting cached within the JDK on the consumer side of the web service.
Within Java, once a DNS is looked up, it caches the IP address via the
networkaddress.cache.ttlproperty in %JRE%\lib\securitySee this link for more:
http://www.rgagnon.com/javadetails/java-0445.html