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Chapter 11. Jetty Logging

Table of Contents

Configuring Jetty Logging
Default Logging with Jetty’s StdErrLog
Configuring Jetty Request Logs
Jetty Logging Integrations (SLF4J, Log4j, Logback, JCL, JUL)
Centralized Logging using Logback
Jetty Dump Tool

This chapter discusses various options for configuring logging.

Configuring Jetty Logging

Jetty provides logging via its own org.eclipse.jetty.util.log.Logger layer, and does not natively use any existing Java logging framework. All logging events, produced via the Jetty logging layer, have a name, a level, and a message. The name is a FQCN (fully qualified class name) similar to how all existing Java logging frameworks operate.

Jetty logging, however, has a slightly different set of levels that it uses internally:

For events serious enough to inform and log, but not fatal.
Informational events.
Debugging events (very noisy).
Exception events that you can safely ignore, but useful for some people. You might see this level as DEBUG under some Java logging framework configurations, where it retains the ignore phrase somewhere in the logging.


Jetty logging produces no FATAL or SEVERE events.

Selecting the Log Framework

Configure the Jetty logging layer via the org.eclipse.jetty.util.log.Log class, following these rules.

  1. Load Properties

    • First from a Classpath Resource called (if found).
    • Then from the System.getProperties().
  2. Determine the log implementation.

    • If property org.eclipse.jetty.util.log.class is defined, load the class it defines as the logger implementation from the server classpath.
    • If the class org.slf4j.Logger exists in server classpath, the Jetty implementation becomes org.eclipse.jetty.util.log.Slf4jLog.
    • If no logger implementation is specified, default to org.eclipse.jetty.util.log.StdErrLog.


You can create your own custom logging by providing an implementation of the Jetty Logger API. For an example of a custom logger, see

The file

By default, the internal Jetty Logging discovery mechanism will load logging specific properties from a classpath resource called and then initialize the Logging from a combination of properties found in that file, along with any System Properties. A typical file will include at least the declaration of which logging implementation you want to use by defining a value for the org.eclipse.jetty.util.log.class property.

Examples for various logging frameworks can be found later in this documentation.

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