Super Cluster solution, part 2nd

Super Cluster solution, part 2nd: Maximizing scalability with WebSphere DMZ Secure Proxy Server, ODR, and WebSphere EXtreme Scale

Because application scalability is an important service quality for most enterprise software topologies, it is common to deploy and execute enterprise-quality java™ee in the Ibm®websphere®application Server network deployment Cluster Application. Although the actual size of the cluster is limited, a useful technique to address this limitation is to achieve the largest possible application scalability, which we call "super clusters." The 1th installment of this two-part series gives a definition of the super cluster and explains how to use it for HTTP plug-ins and proxy servers. In part 2nd of this series, the discussion extends further to the on Demand router (ODR) in the IBM WebSphere DMZ Secure Proxy Server V7 and IBM WebSphere Virtual Enterprise, as well as the IBM Web Sphere EXtreme Scale.

Brief introduction

In the 1th part of the discussion, we concluded that most application scalability issues can be addressed by using the IBM WebSphere application Server cluster. While the scalability requirements of an application rarely exceed the processing power of a single WebSphere application Server cluster, this does happen. The trick that can be used to overcome this potential cluster size limit is to define a hierarchical cluster, or "Super Cluster," as shown in Figure 1.

Figure 1. Super Cluster with hierarchical structure

The essence of the Super cluster is:

Deploy the application to multiple clusters (that is, cluster cluster).

Use the appropriate router to distribute client requests so that, from the client's perspective, a layered cluster consisting of two tiers looks like a flat-structured, single-layer, traditional WebSphere application Server cluster.

The type of router used to distribute client requests directly affects the application of the super cluster and the associated restrictions. Part 1th discusses how to use either the HTTP plug-in or the WebSphere Proxy Server (or both) in the hyper-cluster topology. Part 2nd continues the discussion and expands to discuss the On Demand routers (ODR) and IBM WebS in the IBM WebSphere DMZ Secure Proxy Server V7 and IBM WebSphere Virtual Enterprise Phere EXtreme Scale.

Using the WebSphere DMZ Secure Proxy Server

For security reasons, you may not want to place the proxy server outside of the demilitarized ZONE,DMZ. Part 1th discusses a workaround that uses the HTTP Plug-in (in the DMZ) and the WebSphere Proxy Server (inside the Protocol firewall) to perform the route, as shown in Figure 2.

Figure 2. A WEB server that is routed to a proxy server in the DMZ

Another approach is to take advantage of the WebSphere DMZ Secure Proxy Server V7, as shown in Figure 3.

Figure 3. WebSphere DMZ Secure Proxy Server