Multiple Weblogic nodes on single Windows server - Dispatcher question?

Question

Hi All,
My experience is with other J2EE web servers (SAP's Netweaver predominantly) and typical installations on this platform include the installation of a dispatcher J2EE node which balances load across potentially multiple J2EE nodes on a single server. Does Weblogic have a similar set-up, as it appears when you create multiple nodes in Weblogic, you need to set-up a load balancer to achieve this same effect (that is installed by default on other platforms).
Obviously creating a single node is pretty useless for the majority of production installations; hence what is the recommended option (without setting up a dedicated load balancer) to achieve this on a single (albeit large) server?
Thanks,
Matt

Answer 1

Hi,
I had just remembered another option, we can set up weblogic as webserver which does the load balancing. Below are the two ways you can do that.
1. While creating the domain using "config.sh" you will get an option to set up "weblogic server as webserver". This option is enabled only on condition "cluster must be created, and few managed servers needs to assigned to cluster". For example if we create 3 managed servers and we assign 2 managed to cluster then "Http Proxt screen" would be enabled where remaining server can be set up as "http proxy webserver".
2. Below is the lengthy procedure.
a. Create a standalone weblogic server.
b. We need to create a dummy war, which just contains below "web.xml" adn "weblogic.xml", let me know if you have trouble creating this war file.
Contents of "web.xml"
<?xml version='1.0' encoding='UTF-8'?>
<web-app xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<servlet>
<!-- Add HTTPClusterServlet -->
<servlet-name>HttpClusterServlet</servlet-name>
<servlet-class>weblogic.servlet.proxy.HttpClusterServlet</servlet-class>
<init-param>
<param-name>WebLogicCluster</param-name>
<param-value>127.0.0.1:7003|127.0.0.1:7005|127.0.0.1:7007</param-value>
</init-param>
</servlet>
<!-- Add HTTPClusterServlet Mapping elements -->
<servlet-mapping>
<servlet-name>HttpClusterServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>HttpClusterServlet</servlet-name>
<url-pattern>*.jsp</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>HttpClusterServlet</servlet-name>
<url-pattern>*.htm</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>HttpClusterServlet</servlet-name>
<url-pattern>*.html</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>HttpClusterServlet</servlet-name>
<url-pattern>browsestore</url-pattern>
</servlet-mapping>
</web-app>
Contents of "weblogic.xml" . This deployment descriptor is used to deploy this application as "default application".
<?xml version='1.0' encoding='UTF-8'?>
<weblogic-web-app xmlns="http://www.bea.com/ns/weblogic/90" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<!-- Add the context root here -->
<context-root>/</context-root>
</weblogic-web-app>
c. Now deploy this war file to standalone weblogic server.
d. Lets suppose you had deploy application "vas.war" on managed server "VASMS1", "VASMS2", which are running on host "vasunix1" and "vasunix2" on ports 8002. You can access the application directly "http://vasunix1:8001/vas" or "http://vasunix2:8002/vas".
Now since you had set up "http proxy webserver" which does the load balancing, you can directly hit "http proxy webserver" url and it redirects traffic to "VASMS1" or "VASMS2". Lets suppose "Http proxy webserver" "VASMS3" is running on "vasunix1" on port "8003". You can access the application "http://vasunix1:8003/vas", this request is directed to MS1 or MS2.
I hope this is what you are looking for. Have great day.
Vijay Bheemineni.