title: Jenkins slave on Kubernetes fails to connect tcpSlaveAgentListener/:
body: <p>I am trying to use K8s to set up a Jenkins slave, passing correct agent name and secret but tries to connect to a weird url:</p>
  
  <p>Keeps creating slaves and removing them with the exact same logs.</p>
  
  <p>Master logs:</p>
  
  <pre><code>2020-02-03 21:20:39.980+0000 [id=26]    INFO    o.c.j.p.k.KubernetesCloud#provision: Template for label slave: jenkins-slave
  2020-02-03 21:20:50.005+0000 [id=31]    INFO    hudson.slaves.NodeProvisioner#lambda$update$6: Kubernetes Pod Template provisioning successfully completed. We have now 3 computer(s)
  2020-02-03 21:20:50.026+0000 [id=26914] INFO    o.c.j.p.k.KubernetesLauncher#launch: Created Pod: toks1/jenkins-slave-ncn4x
  2020-02-03 21:20:54.547+0000 [id=26922] INFO    h.TcpSlaveAgentListener$ConnectionHandler#run: Connection #122 failed: java.io.EOFException
  2020-02-03 21:20:54.660+0000 [id=26923] INFO    h.TcpSlaveAgentListener$ConnectionHandler#run: Accepted JNLP4-connect connection #123 from /10.128.0.1:41682
  2020-02-03 21:20:54.864+0000 [id=26914] INFO    o.c.j.p.k.KubernetesLauncher#launch: Pod is running: toks1/jenkins-slave-ncn4x
  2020-02-03 21:20:54.867+0000 [id=26914] INFO    o.c.j.p.k.KubernetesLauncher#launch: Waiting for agent to connect (0/100): jenkins-slave-ncn4x
  2020-02-03 21:20:55.885+0000 [id=26914] INFO    o.c.j.p.k.KubernetesLauncher#launch: Waiting for agent to connect (1/100): jenkins-slave-ncn4x
  2020-02-03 21:20:56.891+0000 [id=26914] INFO    o.c.j.p.k.KubernetesLauncher#launch: Container is terminated jenkins-slave-ncn4x [jnlp]: ContainerStateTerminated(containerID=docker://16631d7785e73264c48e814ae56c337293d7028102e5ce7845bdb8fd96664238, exitCode=255, finishedAt=2020-02-03T21:20:55Z, message=null, reason=Error, signal=null, startedAt=2020-02-03T21:20:53Z, additionalProperties={})
  2020-02-03 21:20:56.927+0000 [id=26914] SEVERE  o.c.j.p.k.KubernetesLauncher#logLastLines: Error in provisioning; agent=KubernetesSlave name: jenkins-slave-ncn4x, template=PodTemplate{inheritFrom='', name='jenkins-slave', namespace='toks1', hostNetwork=false, label='slave', nodeSelector='', nodeUsageMode=EXCLUSIVE, workspaceVolume=EmptyDirWorkspaceVolume [memory=false], containers=[ContainerTemplate{name='slave', image='docker.io/fabstao/jenkins-okd-slave:3', alwaysPullImage=true, workingDir='/home/jenkins/agent', command='', args='', resourceRequestCpu='', resourceRequestMemory='', resourceLimitCpu='', resourceLimitMemory='', envVars=[KeyValueEnvVar [getValue()=http://jenkins-gtsmex:8080 , getKey()=JENKINS_URL], KeyValueEnvVar [getValue()=slave-gts, getKey()=JENKINS_AGENT_NAME], KeyValueEnvVar [getValue()=2a1be5874407a37957eeba186c228c756ac8dbc78f0c4edb735399d15834d5ca, getKey()=JENKINS_SECRET]], livenessProbe=org.csanchez.jenkins.plugins.kubernetes.ContainerLivenessProbe@70ba28dc}]}. Container jnlp exited with error 255. Logs: INFO: Using Remoting version: 3.35
  Feb 03, 2020 9:20:54 PM org.jenkinsci.remoting.engine.WorkDirManager initializeWorkDir
  INFO: Using /home/jenkins/agent/remoting as a remoting work directory
  Feb 03, 2020 9:20:54 PM org.jenkinsci.remoting.engine.WorkDirManager setupLogging
  INFO: Both error and output logs will be printed to /home/jenkins/agent/remoting
  Feb 03, 2020 9:20:54 PM hudson.remoting.jnlp.Main$CuiListener status
  INFO: Locating server among [http://jenkins-gtsmex-toks1.toks1.default.svc.cluster.local/ ]
  Feb 03, 2020 9:20:54 PM hudson.remoting.jnlp.Main$CuiListener error
  SEVERE: Failed to connect to http://jenkins-gtsmex-toks1.toks1.default.svc.cluster.local/tcpSlaveAgentListener/:  jenkins-gtsmex-toks1.toks1.default.svc.cluster.local
  java.io.IOException: Failed to connect to http://jenkins-gtsmex-toks1.toks1.default.svc.cluster.local/tcpSlaveAgentListener/:  jenkins-gtsmex-toks1.toks1.default.svc.cluster.local
      at org.jenkinsci.remoting.engine.JnlpAgentEndpointResolver.resolve(JnlpAgentEndpointResolver.java:206)
      at hudson.remoting.Engine.innerRun(Engine.java:527)
      at hudson.remoting.Engine.run(Engine.java:488)
  Caused by: java.net.UnknownHostException: jenkins-gtsmex-toks1.toks1.default.svc.cluster.local
      at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:184)
      at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
      at java.net.Socket.connect(Socket.java:589)
      at sun.net.NetworkClient.doConnect(NetworkClient.java:175)
      at sun.net.www.http.HttpClient.openServer(HttpClient.java:463)
      at sun.net.www.http.HttpClient.openServer(HttpClient.java:558)
      at sun.net.www.http.HttpClient.&lt;init&gt;(HttpClient.java:242)
      at sun.net.www.http.HttpClient.New(HttpClient.java:339)
      at sun.net.www.http.HttpClient.New(HttpClient.java:357)
      at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:1220)
      at sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1156)
      at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1050)
      at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:984)
      at org.jenkinsci.remoting.engine.JnlpAgentEndpointResolver.resolve(JnlpAgentEndpointResolver.java:203)
      ... 2 more
  </code></pre>
  
  <p>Slave logs:</p>
  
  <pre><code>Feb 03, 2020 9:27:13 PM hudson.remoting.jnlp.Main createEngine
  INFO: Setting up agent: slave-gts
  Feb 03, 2020 9:27:13 PM hudson.remoting.jnlp.Main$CuiListener &lt;init&gt;
  INFO: Jenkins agent is running in headless mode.
  Feb 03, 2020 9:27:13 PM hudson.remoting.Engine startEngine
  INFO: Using Remoting version: 3.40
  Feb 03, 2020 9:27:13 PM hudson.remoting.Engine startEngine
  WARNING: No Working Directory. Using the legacy JAR Cache location: /home/jenkins/.jenkins/cache/jars
  Feb 03, 2020 9:27:14 PM hudson.remoting.jnlp.Main$CuiListener status
  INFO: Locating server among [http://jenkins-gtsmex:8080 ]
  Feb 03, 2020 9:27:14 PM org.jenkinsci.remoting.engine.JnlpAgentEndpointResolver resolve
  INFO: Remoting server accepts the following protocols: [JNLP4-connect, Ping]
  Feb 03, 2020 9:27:14 PM hudson.remoting.jnlp.Main$CuiListener status
  INFO: Agent discovery successful
    Agent address: jenkins-gtsmex
    Agent port:    50000
    Identity:      f5:f7:64:eb:8c:aa:57:81:07:27:2e:38:e1:93:b7:e5
  Feb 03, 2020 9:27:14 PM hudson.remoting.jnlp.Main$CuiListener status
  INFO: Handshaking
  Feb 03, 2020 9:27:14 PM hudson.remoting.jnlp.Main$CuiListener status
  INFO: Connecting to jenkins-gtsmex:50000
  Feb 03, 2020 9:27:14 PM hudson.remoting.jnlp.Main$CuiListener status
  INFO: Trying protocol: JNLP4-connect
  Feb 03, 2020 9:27:14 PM hudson.remoting.jnlp.Main$CuiListener status
  INFO: Remote identity confirmed: f5:f7:64:eb:8c:aa:57:81:07:27:2e:38:e1:93:b7:e5
  Feb 03, 2020 9:27:14 PM hudson.remoting.jnlp.Main$CuiListener status
  INFO: Connected
  </code></pre>
  
  <p>Kubernetes: Openshift OKD 3.11
  Jenkins: 2.218</p>
  
  <p>Please help</p>