INFO: Using Remoting version: 4.3 
Aug 07, 2020 5:31:51 PM org.jenkinsci.remoting.engine.WorkDirManager initializeWorkDir 
INFO: Using /home/jenkins/agent/workspace2/remoting as a remoting work directory 
Aug 07, 2020 5:31:51 PM hudson.remoting.jnlp.Main$CuiListener status 
INFO: Locating server among [***************] 
Aug 07, 2020 5:31:51 PM org.jenkinsci.remoting.engine.JnlpAgentEndpointResolver resolve 
INFO: Remoting server accepts the following protocols: [JNLP4-connect, Ping] 
Aug 07, 2020 5:31:51 PM org.jenkinsci.remoting.engine.JnlpAgentEndpointResolver resolve 
INFO: Remoting TCP connection tunneling is enabled. Skipping the TCP Agent Listener Port availability check 
Aug 07, 2020 5:31:51 PM hudson.remoting.jnlp.Main$CuiListener status 
INFO: Agent discovery successful 
 Agent address: ***********
 Agent port:    **** 
 Identity:      **************
Aug 07, 2020 5:31:51 PM hudson.remoting.jnlp.Main$CuiListener status 
INFO: Handshaking 
Aug 07, 2020 5:31:51 PM hudson.remoting.jnlp.Main$CuiListener status 
INFO: Connecting to ****************
Aug 07, 2020 5:31:51 PM hudson.remoting.jnlp.Main$CuiListener status 
INFO: Trying protocol: JNLP4-connect 
Aug 07, 2020 5:31:51 PM hudson.remoting.jnlp.Main$CuiListener status 
INFO: Remote identity confirmed: *************
Aug 07, 2020 5:31:52 PM hudson.remoting.jnlp.Main$CuiListener status 
INFO: Connected

Aug 07, 2020 5:31:58 PM org.jenkinsci.remoting.engine.WorkDirManager initializeWorkDir
INFO: Using /home/jenkins/agent/workspace1/remoting as a remoting work directory
Aug 07, 2020 5:31:58 PM org.jenkinsci.remoting.engine.WorkDirManager setupLogging
INFO: Both error and output logs will be printed to /home/jenkins/agent/workspace1/remoting
Aug 07, 2020 5:31:58 PM hudson.remoting.jnlp.Main createEngine
INFO: Setting up agent: ws-agent-agent-01
Aug 07, 2020 5:31:58 PM hudson.remoting.jnlp.Main$CuiListener <init>
INFO: Jenkins agent is running in headless mode.
Aug 07, 2020 5:31:58 PM hudson.remoting.Engine startEngine
INFO: Using Remoting version: 4.3
Aug 07, 2020 5:31:58 PM org.jenkinsci.remoting.engine.WorkDirManager initializeWorkDir
INFO: Using /home/jenkins/agent/workspace1/remoting as a remoting work directory
Aug 07, 2020 5:31:59 PM hudson.remoting.jnlp.Main$CuiListener status
INFO: WebSocket connection open
Aug 07, 2020 5:31:59 PM hudson.remoting.jnlp.Main$CuiListener status
INFO: Connected
Aug 07, 2020 5:51:02 PM hudson.slaves.ChannelPinger$1 onDead
INFO: Ping failed. Terminating the channel ws-agent-agent-01.
java.util.concurrent.TimeoutException: Ping started at 1596815222809 hasn't completed by 1596815462809
        at hudson.remoting.PingThread.ping(PingThread.java:133)
        at hudson.remoting.PingThread.run(PingThread.java:89)

INFO: Connected
 WARNING: An illegal reflective access operation has occurred
 WARNING: Illegal reflective access by com.thoughtworks.xstream.core.util.Fields to field java.util.TreeMap.comparator
 WARNING: Please consider reporting this to the maintainers of com.thoughtworks.xstream.core.util.Fields
 WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
 WARNING: All illegal access operations will be denied in a future release
 Oct 04, 2021 7:15:20 AM io.jenkins.remoting.shaded.org.glassfish.tyrus.container.jdk.client.ClientFilter processError
 SEVERE: Connection error has occurred
 java.io.IOException: Connection reset
      at java.base/sun.nio.ch.UnixAsynchronousSocketChannelImpl.finishRead(UnixAsynchronousSocketChannelImpl.java:421)
      at java.base/sun.nio.ch.UnixAsynchronousSocketChannelImpl.finish(UnixAsynchronousSocketChannelImpl.java:193)
      at java.base/sun.nio.ch.UnixAsynchronousSocketChannelImpl.onEvent(UnixAsynchronousSocketChannelImpl.java:215)
      at java.base/sun.nio.ch.EPollPort$EventHandlerTask.run(EPollPort.java:306)|
      at java.base/java.lang.Thread.run(Thread.java:832)
Oct 04, 2021 7:15:20 AM hudson.remoting.jnlp.Main$CuiListener status
 INFO: Read side closed
 Oct 04, 2021 7:15:20 AM hudson.remoting.jnlp.Main$CuiListener status
 INFO: Terminated
 Oct 04, 2021 7:15:21 AM hudson.remoting.Engine lambda$new$1
 SEVERE: Uncaught exception in Engine thread Thread[Thread-0,5,main]
 java.lang.NoClassDefFoundError: jenkins/slaves/restarter/JnlpSlaveRestarterInstaller
        at jenkins.slaves.restarter.JnlpSlaveRestarterInstaller$FindEffectiveRestarters$1.onReconnect(JnlpSlaveRestarterInstaller.java:92)
        at hudson.remoting.EngineListenerSplitter.onReconnect(EngineListenerSplitter.java:54)
        at hudson.remoting.Engine.runWebSocket(Engine.java:687)
        at hudson.remoting.Engine.run(Engine.java:496)
 Caused by: java.lang.ClassNotFoundException: jenkins.slaves.restarter.JnlpSlaveRestarterInstaller
        at java.base/java.net.URLClassLoader.findClass(URLClassLoader.java:435)
        at hudson.remoting.RemoteClassLoader.findClass(RemoteClassLoader.java:215)
        at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:589)
       at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
... 4 more

02:43:59  jenkins-agent-***** was marked offline: Connection was broken: java.nio.channels.ClosedChannelException
02:43:59  	at jenkins.agents.WebSocketAgents$Session.closed(WebSocketAgents.java:142)
02:43:59  	at jenkins.websocket.WebSocketSession.onWebSocketSomething(WebSocketSession.java:91)
02:43:59  	at com.sun.proxy.$Proxy101.onWebSocketClose(Unknown Source)
02:43:59  	at org.eclipse.jetty.websocket.common.events.JettyListenerEventDriver.onClose(JettyListenerEventDriver.java:149)
02:43:59  	at org.eclipse.jetty.websocket.common.WebSocketSession.callApplicationOnClose(WebSocketSession.java:394)
02:43:59  	at org.eclipse.jetty.websocket.common.io.AbstractWebSocketConnection.disconnect(AbstractWebSocketConnection.java:316)
02:43:59  	at org.eclipse.jetty.websocket.common.io.DisconnectCallback.succeeded(DisconnectCallback.java:42)
02:43:59  	at org.eclipse.jetty.websocket.common.io.AbstractWebSocketConnection$CallbackBridge.writeSuccess(AbstractWebSocketConnection.java:86)
02:43:59  	at org.eclipse.jetty.websocket.common.io.FrameFlusher.notifyCallbackSuccess(FrameFlusher.java:359)
02:43:59  	at org.eclipse.jetty.websocket.common.io.FrameFlusher.succeedEntries(FrameFlusher.java:288)
02:43:59  	at org.eclipse.jetty.websocket.common.io.FrameFlusher.succeeded(FrameFlusher.java:280)
02:43:59  	at org.eclipse.jetty.io.WriteFlusher.write(WriteFlusher.java:293)
02:43:59  	at org.eclipse.jetty.io.AbstractEndPoint.write(AbstractEndPoint.java:381)
02:43:59  	at org.eclipse.jetty.websocket.common.io.FrameFlusher.flush(FrameFlusher.java:264)
02:43:59  	at org.eclipse.jetty.websocket.common.io.FrameFlusher.process(FrameFlusher.java:193)
02:43:59  	at org.eclipse.jetty.util.IteratingCallback.processing(IteratingCallback.java:241)
02:43:59  	at org.eclipse.jetty.util.IteratingCallback.iterate(IteratingCallback.java:223)
02:43:59  	at org.eclipse.jetty.websocket.common.io.AbstractWebSocketConnection.outgoingFrame(AbstractWebSocketConnection.java:581)
02:43:59  	at org.eclipse.jetty.websocket.common.io.AbstractWebSocketConnection.close(AbstractWebSocketConnection.java:181)
02:43:59  	at org.eclipse.jetty.websocket.common.io.AbstractWebSocketConnection.onFillable(AbstractWebSocketConnection.java:510)
02:43:59  	at org.eclipse.jetty.websocket.common.io.AbstractWebSocketConnection.onFillable(AbstractWebSocketConnection.java:440)
02:43:59  	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:311)
02:43:59  	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:105)
02:43:59  	at org.eclipse.jetty.io.ChannelEndPoint$1.run(ChannelEndPoint.java:104)
02:43:59  	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:338)
02:43:59  	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:315)
02:43:59  	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:173)
02:43:59  	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:131)
02:43:59  	at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:383)
02:43:59  	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:882)
02:43:59  	at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:1036)
02:43:59  	at java.base/java.lang.Thread.run(Thread.java:829)

Error when executing always post condition:
java.io.IOException: Unable to create live FilePath for jenkins-agent-*****
	at org.jenkinsci.plugins.workflow.support.steps.FilePathDynamicContext.get(FilePathDynamicContext.java:64)
	at org.jenkinsci.plugins.workflow.support.steps.FilePathDynamicContext.get(FilePathDynamicContext.java:47)
	at org.jenkinsci.plugins.workflow.steps.DynamicContext$Typed.get(DynamicContext.java:94)
	at org.jenkinsci.plugins.workflow.cps.ContextVariableSet.get(ContextVariableSet.java:139)
	at org.jenkinsci.plugins.workflow.cps.CpsThread.getContextVariable(CpsThread.java:135)
	at org.jenkinsci.plugins.workflow.cps.CpsStepContext.doGet(CpsStepContext.java:297)
	at org.jenkinsci.plugins.workflow.support.DefaultStepContext.get(DefaultStepContext.java:75)
	at org.jenkinsci.plugins.credentialsbinding.impl.BindingStep$Execution2.doStart(BindingStep.java:123)
	at org.jenkinsci.plugins.workflow.steps.GeneralNonBlockingStepExecution.lambda$run$0(GeneralNonBlockingStepExecution.java:77)
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at java.base/java.lang.Thread.run(Thread.java:829)

pipeline {
    agent {
        label 'agent-pod'
    }
    ...
    stages {
        stage('Init') {
            steps {
                echo "init"
            }
        }
        stage('Tests'){
            agent { 
                label 'Win10'
            }
            steps {
                script {
                    echo "run test"
                    stash name: 'test_report', includes: "test_report.zip"
                }
            }
        }
    }
    post {
        always {
            script { 
                unstash "test_report"
            }
        }
    }
}