Fault Diagnosis Learning Tool: Learning WebSphere Application Server Troubleshooting in practice

Introduction

Troubleshooting WebSphere Application Services has always been one of the most concerned issues for customers. IBM provides a wide range of support for fast problem diagnosis of WebSphere application servers, including helping customers with fast  directing customers to analysis and providing a large number of reference manuals and technical documents, which greatly reduce the workload of problem diagnosis. However, the solution to the problem ultimately depends on the user's analysis of the specific problem. This is like a doctor to the patient, any advanced medical equipment and theoretical knowledge can not replace the doctor's diagnosis, in order to treat patients, doctors should not only have a solid theoretical foundation, but also have a wealth of practical experience, the WebSphere application server for problem diagnosis is the same. So how do you get the experience associated with fault diagnosis? Learning in practice is certainly the best way to gain experience, but it will be a long process to rely solely on solving practical problems at work, and usually at a cost. In contrast, another active approach – experimentation – is much more cost-effective, and experimenting with experience can not only help us to diagnose problems quickly, but it may also be possible to avoid some problems because of the experience. This article will introduce an experimental tool for problem Diagnosis –problem Diagnostics Lab Toolkit (HTTP://WWW.ALPHAWORKS.IBM.COM/TECH/PDTK), which can help us reproduce problems quickly and Guidance for locating and diagnosing.

What is Problem diagnostics Lab Toolkit?

Problem Diagnostics Lab Toolkit (PDLT) is an enterprise application installed on the WebSphere application Server, which is characterized by dynamic modifications that need to run Java code, which Some Java code is written to the JSP through the application, so when the user modifies the corresponding code in the browser, it does not need to restart the application to execute the new code immediately. The JSP that contains the Java code can be invoked through buttons in the actions panel so that it is convenient to modify or run Java code. The monitoring module can help us look at the current state of the system, including thread state, memory and CPU usage, and response times for different requests. PDLT also includes a built-in pressure engine that allows you to set the number of clients to simulate, the number of requests per client, and the time interval between requests two times, when we need to reproduce some of the problems that can be reproduced under pressure conditions. The following figure shows the main functional modules of PDLT:

Figure 1. Functional modules for PDLT