Default environment variables

You can configure Open Liberty environment variables in your server.env file to customize the Open Liberty environment. The ${wlp.install.dir} configuration variable has an inferred location that is set to the parent of the directory that contains the launch script.

For more information about the server.env file, see Server configuration overview: server.env.

The following table lists the default Open Liberty environment variables and gives a brief description for each variable:

Open Liberty default environment variables
Environment VariableDescription


Indicates which Java runtime environment (JRE) to use. If this variable is not set, the system default is used.


A list of command-line options, such as system properties or -X parameters, that are passed to the JVM when the server starts. Any values that contain spaces must be enclosed in quotes.


The directory that contains the log file. The default value is %WLP_OUTPUT_DIR%/serverName/logs.


The log file name. This log file is used only if the server start command is run in the background through the start action.


The directory that contains output files from the JVM that the server uses, such as the javadump files. The default value is the ${WLP_OUTPUT_DIR}/serverName location. If this variable is set to a relative path, the resulting path is relative to this default location. For example, a value of SERVER_WORKING_DIR=logs/javadumps results in a path of ${WLP_OUTPUT_DIR}/serverName/logs/javadumps.


The directories that contain files to be loaded as configuration variables. The default value is ${server.config.dir}/variables. To define a list of directories as the value for this variable, separate each directory with the path separator for your operating system. For Windows, the path separator is a semicolon (;). For Unix-based systems, the path separator is a colon (:).


The user or custom configuration directory that is used to store shared and server-specific configuration. See the path_to_liberty/wlp/README.TXT file for details about shared resource locations. A server configuration is at the %WLP_USER_DIR%/servers/serverName location. The default value is the user directory in the installation directory.


The directory that contains output files for defined servers. This directory must have both read and write permissions for the user or users who start servers. By default, the server output logs and work area are stored at the %WLP_USER_DIR%/servers/serverName location alongside configuration and applications. If this variable is set, the output logs and work area are stored at the %WLP_OUTPUT_DIR%/serverName location.


The port to use for running the server in debug mode. The default value is 7777.


Specifies whether to suspend the JVM on startup. This variable can be set to y to suspend the JVM on startup until a debugger attaches, or set to n to start up without waiting for a debugger to attach. The default value is y.


Specifies whether to allow remote debugging. This variable can be set to y to allow remote debugging. By default, this value is not defined, which does not allow remote debugging on newer JDKs and JREs.