Verbose Logging in WebSphere Liberty Server

Verbose Logging in WebSphere Liberty Server | Generated by AI

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To address your query about the verbose log option for the server command in WebSphere Liberty Profile (WLP), let’s clarify what the server command does and how verbosity can be controlled.

The server command in WLP is used to manage server instances, with actions like start, stop, run, or status. For example:

server start <serverName> starts the server in the background, with output redirected to log files (e.g., logs/console.log).
server run <serverName> starts the server in the foreground, displaying output directly in the terminal.

Your question asks about a “verbose log option” for the server command, which could imply either more detailed output from the command itself or more detailed logging from the server it manages. After exploring the options, it’s clear that the server command does not have a direct flag like --verbose or -v to increase its own output verbosity. Instead, verbosity pertains to the server’s logging behavior, which can be influenced when invoking the command.

Enabling Verbose Logging

In WLP, the verbosity of logs is controlled through the server’s logging configuration, not directly via a server command flag. Here’s how you can enable verbose logging:

1. Configure Logging in `server.xml`

The primary way to enable verbose logging is by adjusting the <logging> element in the server’s server.xml file, typically located in <WLP_HOME>/usr/servers/<serverName>/. You can set a detailed trace specification to increase log verbosity. For example:

<logging traceSpecification="*=all" />

*=all enables all trace points, making the logs extremely verbose (useful for debugging).
For more targeted verbosity, you can specify components, e.g., *=info:com.example.*=debug, setting the default level to info but debug for the com.example package.

Other useful attributes include:

logLevel: Sets the general log level (e.g., INFO, DEBUG, TRACE).
consoleLogLevel: Controls the level of messages written to console.log or the terminal (e.g., DEBUG or TRACE).

Example with a finer console level:

<logging consoleLogLevel="DEBUG" traceSpecification="*=audit" />

When you run server start, the logs (including verbose output) go to logs/console.log. With server run, this verbose output appears directly in your terminal.

2. Use Environment Variables

You can also control log verbosity via environment variables, which override or complement server.xml settings. For instance, set the WLP_LOGGING_CONSOLE_LOGLEVEL variable before running the server command:

export WLP_LOGGING_CONSOLE_LOGLEVEL=DEBUG
server start <serverName>

This sets the console log level to DEBUG, ensuring more detailed output.
Valid levels include INFO, DEBUG, FINE, FINER, FINEST, etc.

For server run, this will make the terminal output more verbose; for server start, it affects console.log.

3. JVM-Specific Verbose Options

If you’re interested in specific verbose outputs like garbage collection logs, you can add JVM options (though this is server runtime-related, not the server command itself). Add -verbose:gc to the jvm.options file in <WLP_HOME>/usr/servers/<serverName>/, or include it via server.xml:

<jvmEntries verbose="gc" />

This generates GC-related logs, typically in console.log or the terminal with server run.

How This Relates to the `server` Command

No Direct --verbose Option: The server command itself (e.g., server start) doesn’t have a --verbose or similar flag to detail its execution steps beyond basic status messages (e.g., “Server started”).
Server Logging Controls Verbosity: The verbosity you see depends on the server’s logging configuration. Use server run to observe logs live in the terminal, or check log files after server start.

For example:

With <logging traceSpecification="*=all"/> in server.xml, running server run <serverName> floods the terminal with detailed logs.
With server start <serverName>, the same verbosity appears in logs/console.log.

Recommendation

To achieve verbose logging when using the server command:

Edit server.xml to include a detailed traceSpecification (e.g., *=all for maximum verbosity or a specific level like *=debug).
Alternatively, set WLP_LOGGING_CONSOLE_LOGLEVEL=DEBUG in your environment.
Use server run to see the verbose output directly, or server start and check logs/console.log.

This approach ensures you get the detailed logs you need, tailored to your debugging or monitoring requirements.

If you meant something more specific (e.g., command execution verbosity rather than server logs), feel free to clarify! Otherwise, configuring the server’s logging as described is the standard way to enable verbose logging with the server command in WLP.

Note: Be careful with the logs directory. It contains logs, such as trace files.

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