[standalone@localhost:9990 /] /deployment=testwebapplication.war/subsystem=logging/configuration=default/logger=unknown:read-attribute(name=level
{
    "outcome" => "failed",
    "result" => undefined,
    "failure-description" => "WFLYCTL0158: Operation handler failed: java.lang.NullPointerException",
    "rolled-back" => true
}

17:11:30,742 ERROR [org.jboss.as.controller.management-operation] (management-handler-thread - 1) WFLYCTL0013: Operation ("read-attribute") failed - address: ([
    ("deployment" => "testwebapplication.war"),
    ("subsystem" => "logging"),
    ("configuration" => "default"),
    ("logger" => "unknown")
]): java.lang.NullPointerException
        at org.jboss.as.logging.deployments.resources.LoggerResourceDefinition$1.updateModel(LoggerResourceDefinition.java:77)
        at org.jboss.as.logging.deployments.resources.LoggerResourceDefinition$LoggerConfigurationReadStepHandler.updateModel(LoggerResourceDefinition.java:105)
        at org.jboss.as.logging.deployments.resources.LoggingConfigurationReadStepHandler.execute(LoggingConfigurationReadStepHandler.java:51)
        at org.jboss.as.controller.operations.global.ReadAttributeHandler.doExecuteInternal(ReadAttributeHandler.java:174)
        at org.jboss.as.controller.operations.global.ReadAttributeHandler.doExecute(ReadAttributeHandler.java:133)
        at org.jboss.as.controller.operations.global.GlobalOperationHandlers$AbstractMultiTargetHandler.execute(GlobalOperationHandlers.java:230)
        at org.jboss.as.controller.AbstractOperationContext.executeStep(AbstractOperationContext.java:951)
        at org.jboss.as.controller.AbstractOperationContext.processStages(AbstractOperationContext.java:694)
        at org.jboss.as.controller.AbstractOperationContext.executeOperation(AbstractOperationContext.java:389)
        at org.jboss.as.controller.OperationContextImpl.executeOperation(OperationContextImpl.java:1363)
        at org.jboss.as.controller.ModelControllerImpl.internalExecute(ModelControllerImpl.java:410)
        at org.jboss.as.controller.ModelControllerImpl.execute(ModelControllerImpl.java:232)
        at org.jboss.as.controller.remote.ModelControllerClientOperationHandler$ExecuteRequestHandler.doExecute(ModelControllerClientOperationHandler.java:213)
        at org.jboss.as.controller.remote.ModelControllerClientOperationHandler$ExecuteRequestHandler.access$300(ModelControllerClientOperationHandler.java:136)
        at org.jboss.as.controller.remote.ModelControllerClientOperationHandler$ExecuteRequestHandler$1$1.run(ModelControllerClientOperationHandler.java:157)
        at org.jboss.as.controller.remote.ModelControllerClientOperationHandler$ExecuteRequestHandler$1$1.run(ModelControllerClientOperationHandler.java:153)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:422)
        at org.jboss.as.controller.AccessAuditContext.doAs(AccessAuditContext.java:149)
        at org.jboss.as.controller.remote.ModelControllerClientOperationHandler$ExecuteRequestHandler$1.execute(ModelControllerClientOperationHandler.java:153)
        at org.jboss.as.protocol.mgmt.ManagementRequestContextImpl$1.doExecute(ManagementRequestContextImpl.java:70)
        at org.jboss.as.protocol.mgmt.ManagementRequestContextImpl$AsyncTaskRunner.run(ManagementRequestContextImpl.java:160)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at java.lang.Thread.run(Thread.java:745)
        at org.jboss.threads.JBossThread.run(JBossThread.java:320)

[standalone@localhost:9990 /] /subsystem=logging/logger=unknown:read-attribute(name=level
{
    "outcome" => "failed",
    "failure-description" => "WFLYCTL0216: Management resource '[
    (\"subsystem\" => \"logging\"),
    (\"logger\" => \"unknown\")
]' not found",
    "rolled-back" => true
}