Configuring and Using the WebLogic Diagnostics Framework

Introduction and Roadmap

The following sections describe the contents and audience for this guide—Configuring and Using the WebLogic Diagnostic Framework:

What Is the WebLogic Diagnostic Framework?

The WebLogic Diagnostic Framework (WLDF) is a monitoring and diagnostic framework that defines and implements a set of services that run within BEA WebLogic Server® processes and participate in the standard server life cycle. Using WLDF, you can create, collect, analyze, archive, and access diagnostic data generated by a running server and the applications deployed within its containers. This data provides insight into the run-time performance of servers and a

WLDF includes several components for collecting and analyzing data:

Diagnostic Image Capture—Creates a diagnostic snapshot from the server that can be used for post-failure analysis.
Archive—Captures and persists data events, log records, and metrics from server instances and applications.
Instrumentation—Adds diagnostic code to WebLogic Server instances and the applications running on them to execute diagnostic actions at specified locations in the code. The Instrumentation component provides the means for associating a diagnostic context with requests so they can be tracked as they flow through the system.
Harvester—Captures metrics from run-time MBeans, including WebLogic Server MBeans and custom MBeans, which can be archived and later accessed for viewing historical data.
Watches and Notifications—Provides the means for monitoring server and application states and sending notifications based on criteria set in the watches.
Logging services—Manages logs for monitoring server, subsystem, and application events. The WebLogic Server logging services are documented separately from the rest of the WebLogic Diagnostic Framework. See Configuring Log Files and Filtering Log Messages.

WLDF provides a set of standardized application programming interfaces (APIs) that enable dynamic access and control of diagnostic data, as well as improved monitoring that provides visibility into the server. Independent Software Vendors (ISVs) can use these APIs to develop custom monitoring and diagnostic tools for integration with WLDF.

WLDF was a new feature in WebLogic Server 9.0. WLDF enables dynamic access to server data through standard interfaces, and the volume of data accessed at any given time can be modified without shutting down and restarting the server.

Document Scope and Audience

This document describes and tells how to configure and use the monitoring and diagnostic services provided by WLDF.

WLDF provides features for monitoring and diagnosing problems in running WebLogic Server instances and clusters and in applications deployed to them. Therefore, the information in this document is directed both to system administrators and to application developers. It also contains information for third-party tool developers who want to build tools to support and extend WLDF.

It is assumed that readers are familiar with Web technologies and the operating system and platform where WebLogic Server is installed.

Guide to This Document

This document is organized as follows:

This chapter, "Introduction and Roadmap," provides an overview of WLDF components and describes the audience for this guide.
Overview of the WLDF Architecture, provides a high-level view of the WLDF architecture.
Understanding WLDF Configuration, provides an overview of how WLDF features are configured for servers and applications.
Configuring and Capturing Diagnostic Images, describes how to configure and use the WLDF Diagnostic Image Capture component to capture a snapshot of significant server configuration settings and state.
Configuring Diagnostic Archives, describes how to configure and use the WLDF Diagnostic Archive component to persist diagnostic data to a file store or database.
Configuring the Harvester for Metric Collection, describes how to configure and use the WLDF Harvester component to harvest metrics from runtime MBeans, including WebLogic Server MBeans and custom MBeans.
Configuring Watches and Notifications, provides an overview of WLDF watches and notifications.
Configuring Watches, describes how to configure watches to monitor server instances and applications for specified conditions and then send notifications when those conditions are met.
Configuring Notifications, describes how to configure notifications that can be triggered by watches.
Configuring Instrumentation, describes how to add diagnostic instrumentation code to WebLogic Server classes and to the classes of applications running on the server.
Configuring the DyeInjection Monitor to Manage Diagnostic Contexts, describes how to use the DyeInjection monitor and how to use dye filtering with diagnostic monitors.
Accessing Diagnostic Data With the Data Accessor, tells how to use the WLDF Data Accessor component to retrieve diagnostic data.
Configuring and Using WLDF Programmatically, provides an overview of how you can use the JMX API and the WebLogic Scripting Tool (weblogic.WLST) to configure and use WLDF components.
WLDF Query Language, describes the WLDF query language that is used for constructing expressions to query diagnostic data using the Data Accessor, construct watch rules, and construct rules for filtering logs.
WLDF Instrumentation Library, describes the predefined diagnostic monitors and diagnostic actions that are included in the WLDF Instrumentation Library.
WebLogic Scripting Tool Examples, provides examples of how to perform WLDF monitoring and diagnostic activities using the WebLogic Scripting Tool.
Terminology, is a glossary of terms used in WLDF.

Samples and Tutorials

In addition to this document, BEA Systems provides a variety of samples and tutorials that show WLDF configuration and use.

Avitek Medical Records Application (MedRec) and Tutorials

MedRec is an end-to-end sample J2EE application shipped with WebLogic Server that simulates an independent, centralized medical record management system. The MedRec application provides a framework for patients, doctors, and administrators to manage patient data using a variety of different clients.

MedRec demonstrates WebLogic Server and J2EE features, and highlights BEA-recommended best practices. MedRec is included in the WebLogic Server distribution, and can be accessed from the Start menu on Windows machines. For Linux and other platforms, you can start MedRec from the WL_HOME\samples\domains\medrec directory, where WL_HOME is the top-level installation directory for WebLogic Platform.

New and Changed Features in this Release

The WebLogic Diagnostic Framework was introduced in WebLogic Server 9.0. The following features are new in this release.

Hot-Swap Support When Using Deployment Plans

WebLogic Server supports deployment plans, as specified in the J2EE Deployment Specification API (JSR-88). With deployment plans, you can modify an application's configuration after the application is built, without having to modify the application archives.

In release 9.0, you had to redeploy an application after making changes to its diagnostic configuration, even when using a deployment plan.

In WebLogic Server 9.1, WLDF supports a feature called "hot swap" when using deployment plans. If you enable hot swap and then deploy your application with a deployment plan, you can dynamically update diagnostic instrumentation settings without redeploying the application.

See Using Deployment Plans for Dynamically Controlling Instrumentation Configuration.

WLDF Console Extension

The WebLogic Diagnostic Framework (WLDF) Console Extension is an extension that you can add to the WebLogic Server Administration Console. It provides views and tools for graphically presenting ("visualizing") diagnostic data in charts and graphs. See Using the WebLogic Diagnostic Framework Console Extension.