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 applications and enables you to isolate and diagnose faults when they occur.
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—Manage 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 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.
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.
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 following features are new to the WebLogic Diagnostic Framework in this release.
There is a new standard application-scoped monitor, HttpSessionDebug, which you can use to inspect an HTTP Session object. For more information, see the entry for HttpSessionDebug in Diagnostic Monitor Library.
The WebLogic Diagnostic Framwork Console Extension also has new features. See Introduction and Roadmap in Using the WebLogic Diagnostic Framwork Console Extension.