Our application team trying to make a connection from their agents to Jenkins master. The initial connectivity was good and after an amount of time, we see a disruption. 

The build nodes succeeded to be connected to the Jenkins master, but sometimes the Jenkins master does not reply back (showing timeout). We are using WebSocket method.

Jenkins version: 2.319.1 (LTS)

Launch method: Launch agent by connecting it to the controller.

Agent name: HSM - Pipe Plaza

Agent version: 4.11.2

JDK version: 1.8

Agent logs: Refer to the attachment

Jenkins Master logs: Refer to the attachment. 

2021-12-21 04:20:34.830+0000 [id=181293] INFO j.s.DefaultJnlpSlaveReceiver#channelClosed: Jetty (winstone)-181293 for HSM - Dry Dry Desert terminated: java.nio.channels.ClosedChannelException

While agent connection we can see below Warning in the logs. May I know what this warning refers.

2021-12-21 04:25:21.601+0000 [id=181571] WARNING hudson.model.Slave#reportLauncherCreateError: Issue with creating launcher for agent HSM - Grumble Volcano. The agent has not been fully initialized yetProbably there is a race condition with Agent reconnection or disconnection, check other log entries
java.lang.IllegalStateException: No remoting channel to the agent OR it has not been fully initialized yet
at hudson.model.Slave.reportLauncherCreateError(Slave.java:540)
at hudson.model.Slave.createLauncher(Slave.java:512)
at org.jenkinsci.plugins.workflow.support.DefaultStepContext.makeLauncher(DefaultStepContext.java:160)
at org.jenkinsci.plugins.workflow.support.DefaultStepContext.get(DefaultStepContext.java:83)
at org.jenkinsci.plugins.docker.workflow.WithContainerStep$Callback.finished(WithContainerStep.java:391)
at org.jenkinsci.plugins.workflow.steps.BodyExecutionCallback$TailCall.onFailure(BodyExecutionCallback.java:128)
at org.jenkinsci.plugins.workflow.cps.CpsBodyExecution$FailureAdapter.receive(CpsBodyExecution.java:361)
at com.cloudbees.groovy.cps.impl.ThrowBlock$1.receive(ThrowBlock.java:68)
at com.cloudbees.groovy.cps.impl.ConstantBlock.eval(ConstantBlock.java:21)
at com.cloudbees.groovy.cps.Next.step(Next.java:83)
at com.cloudbees.groovy.cps.Continuable$1.call(Continuable.java:174)
at com.cloudbees.groovy.cps.Continuable$1.call(Continuable.java:163)
at org.codehaus.groovy.runtime.GroovyCategorySupport$ThreadCategoryInfo.use(GroovyCategorySupport.java:129)
at org.codehaus.groovy.runtime.GroovyCategorySupport.use(GroovyCategorySupport.java:268)
at com.cloudbees.groovy.cps.Continuable.run0(Continuable.java:163)
at org.jenkinsci.plugins.workflow.cps.SandboxContinuable.access$001(SandboxContinuable.java:18)
at org.jenkinsci.plugins.workflow.cps.SandboxContinuable.run0(SandboxContinuable.java:51)
at org.jenkinsci.plugins.workflow.cps.CpsThread.runNextChunk(CpsThread.java:185)
at org.jenkinsci.plugins.workflow.cps.CpsThreadGroup.run(CpsThreadGroup.java:402)
at org.jenkinsci.plugins.workflow.cps.CpsThreadGroup.access$400(CpsThreadGroup.java:96)
at org.jenkinsci.plugins.workflow.cps.CpsThreadGroup$2.call(CpsThreadGroup.java:314)
at org.jenkinsci.plugins.workflow.cps.CpsThreadGroup$2.call(CpsThreadGroup.java:278)
at org.jenkinsci.plugins.workflow.cps.CpsVmExecutorService$2.call(CpsVmExecutorService.java:67)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at hudson.remoting.SingleLaneExecutorService$1.run(SingleLaneExecutorService.java:139)
at jenkins.util.ContextResettingExecutorService$1.run(ContextResettingExecutorService.java:28)
at jenkins.security.ImpersonatingExecutorService$1.run(ImpersonatingExecutorService.java:68)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)