NPE happens randomly knocking the instance off line and has to be restarted.

[Server:server-one] 13:03:37,900 ERROR [org.jboss.as.controller.management-operation] (ServerService Thread Pool – 1) WFLYCTL0013: Operation ("clean-obsolete-content") failed - address: ([]): java.lang.NullPointerException
[Server:server-one] at org.jboss.as.repository.ContentRepository$Factory$ContentRepositoryImpl.listLocalContents(ContentRepository.java:428)
[Server:server-one] at org.jboss.as.repository.ContentRepository$Factory$ContentRepositoryImpl.cleanObsoleteContent(ContentRepository.java:390)
[Server:server-one] at org.jboss.as.server.mgmt.domain.RemoteFileRepositoryService.cleanObsoleteContent(RemoteFileRepositoryService.java:160)
[Server:server-one] at org.jboss.as.server.operations.CleanObsoleteContentHandler.execute(CleanObsoleteContentHandler.java:76)
[Server:server-one] at org.jboss.as.controller.AbstractOperationContext.executeStep(AbstractOperationContext.java:803)
[Server:server-one] at org.jboss.as.controller.AbstractOperationContext.doCompleteStep(AbstractOperationContext.java:601)
[Server:server-one] at org.jboss.as.controller.AbstractOperationContext.completeStepInternal(AbstractOperationContext.java:354)
[Server:server-one] at org.jboss.as.controller.AbstractOperationContext.executeOperation(AbstractOperationContext.java:330)
[Server:server-one] at org.jboss.as.controller.OperationContextImpl.executeOperation(OperationContextImpl.java:1183)
[Server:server-one] at org.jboss.as.controller.ModelControllerImpl.internalExecute(ModelControllerImpl.java:362)
[Server:server-one] at org.jboss.as.controller.ModelControllerImpl.execute(ModelControllerImpl.java:205)
[Server:server-one] at org.jboss.as.controller.ModelControllerImpl$3.execute(ModelControllerImpl.java:626)
[Server:server-one] at org.jboss.as.controller.ModelControllerImpl$3.execute(ModelControllerImpl.java:616)
[Server:server-one] at org.jboss.as.server.deployment.ContentRepositoryCleaner.cleanObsoleteContent(ContentRepositoryCleaner.java:132)
[Server:server-one] at org.jboss.as.server.deployment.ContentRepositoryCleaner$ContentRepositoryCleanerTask.run(ContentRepositoryCleaner.java:67)
[Server:server-one] at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
[Server:server-one] at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:304)
[Server:server-one] at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:178)
[Server:server-one] at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
[Server:server-one] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
[Server:server-one] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
[Server:server-one] at java.lang.Thread.run(Thread.java:745)
[Server:server-one] at org.jboss.threads.JBossThread.run(JBossThread.java:320)
[Server:server-one]
[Server:server-one] 13:03:37,931 ERROR [org.jboss.as.server] (ServerService Thread Pool – 1) WFLYSRV0216: Error cleaning obsolete content WFLYCTL0158: Operation handler failed: java.lang.NullPointerException