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Test database connections and set server stop time out in Open Liberty

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Michal Broz on Mar 7, 2023
Post available in languages: 日本語 ,

Open Liberty introduces a new capability to test database connections with the Admin Center Server Config tool. The server stop command adds the the --timeout option to specify the maximum amount of time to wait for the server to stop. This release also provides many significant bug fixes, including one that addresses a CVE in Jakarta RESTful Web Services 3.0 feature.

In Open Liberty

Along with the new features and functions added to the runtime, we’ve also made updates to our guides.

View the list of fixed bugs in

Run your apps using

If you’re using Maven, here are the coordinates:


Or for Gradle:

dependencies {
    libertyRuntime group: 'io.openliberty', name: 'openliberty-runtime', version: '[,)'

Or if you’re using Docker:

FROM open-liberty

Or take a look at our Downloads page.

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Test database connections using Admin Center

Looking for a simple way to test your database connections? With this release, you can now validate your connections using the Liberty Admin Center feature. The connection test exercises the same code paths as your applications, giving you confidence in your server configuration. The Admin Center connection validation feature is enabled by the same REST APIs featured in the Testing database connections in Open Liberty apps with REST APIs blog post.

To enable database connection testing, the following minimum set of features must be present in your server configuration:


Although this example uses the mpOpenApi-3.0 feature, you can use any MicroProfile OpenAPI version that is compatible with your other features.

To provide an example, we’ll start by testing the server resource DefaultDataSource, which is configured to connect to a Derby database using container authentication with an authentication alias.

The following sample server.xml file enables the features to configure the Admin Center test connection function and configures the connection to the Derby database:

<server description="new server">

    <!-- Enable features -->

    <!-- To access this server from a remote client add a host attribute to the following element, e.g. host="*" -->
    <httpEndpoint id="defaultHttpEndpoint" httpPort="9080" httpsPort="9443"/>

    <library id="derby">
      <file name="${server.config.dir}/derby/derby.jar"/>

    <dataSource id="DefaultDataSource">
      <jdbcDriver libraryRef="derby"/>
      <!-- Example properties referencing an in-memory Derby Embedded database -->
      <properties.derby.embedded databaseName="memory:defaultdb" createDatabase="create"/>

    <authData id="myAuth" user="dbuser" password="dbpass"/>

    <!-- Default SSL configuration enables trust for default certificates from the Java runtime -->
    <ssl id="defaultSSLConfig" trustDefaultCerts="true"/>


    <basicRegistry id="basic">
       <user name="admin" password="adminpwd"/>

    <!-- Assign 'admin' to Administrator -->


For this server.xml example, you will need to add the Derby JAR to the server configuration or use your own database configuration.

  1. Configure a Liberty server using the example server.xml file for guidance and then start the server. After the server is started, you can check the logs to find the URL to navigate to the Admin Center. In the previous example, you can navigate to the Admin Center using the https://localhost:9443/adminCenter/ URL.

  2. In the Admin Center UI, select the Server Config tool.

    Server Config Tool
  3. Select server.xml to edit.

  4. In the Design > Server menu, navigate to the resource you want to test and click the Test button.

    Select resource
  5. Choose the type of authentication your application uses:

    • For applications that use container authentication, choose the Container authentication tab and select whether to use default authentication, specify an authentication alias, or choose a login module configuration.

      For this example, the configuration doesn’t specify default authentication on the dataSource element or configure any login modules. Therefore, you must specify an authentication alias by using the drop-down field.

      Container authentication
    • For applications that use application authentication, choose the Application authentication tab and fill in a valid username and password for the database resource.

      Application authentication
    • If your application does not use a resource reference and the server.xml doesn’t include enableContainerAuthForDirectLookups="true" in the connectionManager element, then choose the No resource reference tab and fill in a valid username and password for the database resource.

    No Resource Reference
  6. Click the Connection Test button to run the test and display the results. The following example shows a successful connection test:

Successful connection test example

In addition to Java Database Connectivity, you can also test connections to Jakarta Connectors, Jakarta Messaging and Cloudant Integration resources.

For more information about administering Liberty using a GUI, refer to the Manage Open Liberty with Admin Center documentation.

Specify how long to wait for the server to stop

Open Liberty introduces a --timeout command line option for the server stop command. You can use this option to specify the maximum amount of time the server stop command waits for confirmation that the server has stopped.

Prior to this update, the default maximum waiting period of 30 seconds could not be adjusted.

The timeout value can be specified in minutes (m), seconds (s), or a combination of both. When a unit is not specified, the default of seconds is used. Minutes and seconds can be combined, for example 2m30s, which means 2 minutes and 30 seconds. Examples:

   ./server stop                   // 30 seconds
   ./server stop --timeout=45      // 45 seconds
   ./server stop --timeout=45s     // 45 seconds
   ./server stop --timeout=3m20s   // 3 minutes, 20 seconds

The default timeout value is 30 seconds. If the server consistently takes longer than 30 seconds to stop, consider increasing the timeout value by using the --timeout option.

For more information, refer to the server stop command documentation.

Security vulnerability (CVE) fixes in this release

CVE CVSS Score Vulnerability Assessment Versions Affected Notes



Information disclosure -

Affects the restfulWS-3.0 feature

For a list of past security vulnerability fixes, reference the Security vulnerability (CVE) list.

Notable bugs fixed in this release

We’ve spent some time fixing bugs. The following sections describe just some of the issues resolved in this release. If you’re interested, here’s the full list of bugs fixed in

  • Server fails to start due to conflict on servlet feature

    When individually installing a set of EE7 or EE8 features using the featureUtility installFeature command, the server can fail to start due to a conflict on servlet features, as shown in the following example.            E CWWKF0033E: The singleton features servlet-3.1 and servlet-3.0 cannot be loaded at the same time.  The configured features servlet-3.1 and apiDiscovery-1.0 include one or more features that cause the conflict. Your configuration is not supported; update server.xml to remove incompatible features.                I FFDC1015I: An FFDC Incident has been created: "java.lang.IllegalArgumentException: Unable to load conflicting versions of features "" and "".  The feature dependency chains that led to the conflict are: and -> -> io.openliberty.restHandler.internal-1.0 -> io.openliberty.webBundleSecurity.internal-1.0 -> io.openliberty.servlet.internal-3.0 ->

    The problem does not occur if the featureUtility installServerFeatures command is used instead. It can also be worked around by installing the mpJwt-1.2 feature if using Jakarta EE 8 features.

    The issue has been resolved and the featureUtility installFeature command will install the features in a way to allow all of them to be included in a server.xml and the server will be able to start properly.

  • Scheduled Futures leak resources from Managed Executor Services on application stop

    The futures queue in ManagedScheduledExecutorServiceImpl holds references to scheduled futures, even once they have completed.

    The queue is periodically cleaned when new tasks are scheduled, by the private purgeFutures() method, but otherwise they are not actively removed, and it isn’t called when applications are shutdown. As purgeFutures() is private, applications can’t call it themselves.

    This issue has been resolved and the resources are now released automatically when an application stops.

  • Validate HTTP header names

    Due to a bug, HTTP requests were not being checked for invalid characters.

    The issue has been resolved and an HTTP request with an invalid character now causes the HTTP response to contain a 400 response code.

  • DoNotAllowDuplicateSetCookies http channel config option is not working

    The HTTP channel config property DoNotAllowDuplicateSetCookies=true, when set, still allows duplicate Set-Cookie cookies in HTTP responses.

    This issue has been resolved and the response headers no longer contain the duplicate Set-Cookie cookies when DoNotAllowDuplicateSetCookies=true is set.

  • batch-2.1 feature content is active even when configuring batch-1.0 or 2.0

    Content added as part of the beta batch-2.1 feature will be loaded and active even if the user configures the server for batch-1.0 or batch-2.0. This is unintended and may cause conflicts based on the user’s environment.

    The issue has been resolved and the new batch-2.1 specific content will no longer be exposed in batch-1.0 nor batch-2.0 features.

  • Fix configuration attribute name used in CWWKS1738E message

    When using an OIDC RP via the Social Media Login feature, it’s possible for the wrong configuration attribute name to be included in the error message emitted when the expected user name claim is not in the ID token returned from the OP. The following is an example of such an error message. E CWWKS1738E: The OpenID Connect client [client01] failed to authenticate the JSON Web Token because the claim [someBadName] specified by the [userIdentifier] configuration attribute was not included in the token.

    The error message refers to the userIdentifier configuration attribute. However, in the socialLogin-1.0 feature the equivalent configuration attribute is actually called userNameAttribute.

    This issue has been resolved by updating the NLS message to reference the correct attribute name.

New and updated guides since the previous release

As Open Liberty features and functionality continue to grow, we continue to add new guides to on those topics to make their adoption as easy as possible. Existing guides also receive updates to address any reported bugs/issues, keep their content current, and expand what their topic covers.

Application authentication

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