"Different jenkins master URL" doesn't work

[janisBerz]

I have set "Different jenkins master URL" to bypass or proxy but once the container starts it uses "Jenkins URL" as Jenkins server URL.

Environment:
Jenkins 2.89
Yet another Docker plug-in 0.1.0-rc47

Windows container log:
###################################
JENKINS_URL = https://no-proxy.com
JENKINS_USER =
JENKINS_HOME = c:\jenkins
COMPUTER_URL = computer/VH-WinDockerHost-2e30e1cf5b58/
COMPUTER_SECRET = xxx
NO_CERTIFICATE_CHECK = true
JAVA_OPTS =
SLAVE_OPTS =
###################################
Invoke-WebRequest -Uri https://no-proxy.com/jnlpJars/slave.jar -Outfile c:\jenkins/slave.jar
java -jar c:\jenkins/slave.jar -noReconnect -noCertificateCheck -jnlpUrl https://no-proxy.com/computer/VH-WinDockerHost-2e30e1cf5b58//slave-agent.jnlp -secret xxx
Skipping HTTPS certificate checks altogether. Note that this is not secure at all.
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main createEngine
INFO: Setting up slave: VH-WinDockerHost-2e30e1cf5b58
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener
INFO: Jenkins agent is running in headless mode.
Jun 20, 2018 9:33:23 AM hudson.remoting.Engine startEngine
WARNING: No Working Directory. Using the legacy JAR Cache location: C:\Users\ContainerAdministrator.jenkins\cache\jars
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener status
INFO: Locating server among [https://proxy.com/, https://no-proxy.com/]
Jun 20, 2018 9:33:23 AM org.jenkinsci.remoting.engine.JnlpAgentEndpointResolver resolve
INFO: Remoting server accepts the following protocols: [JNLP4-connect, Ping]
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener status
INFO: Agent discovery successful
Agent address: proxy.com
Agent port: 3698
Identity: xxx
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener status
INFO: Handshaking
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener status
INFO: Connecting to proxy.com:3698
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener status
INFO: Trying protocol: JNLP4-connect
Jun 20, 2018 9:33:23 AM org.jenkinsci.remoting.protocol.impl.AckFilterLayer abort
WARNING: [JNLP4-connect connection to proxy.com/172.16.0.6:3698] Incorrect acknowledgement sequence, expected 0x000341434b got 0x485454502f
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener status
INFO: Protocol JNLP4-connect encountered an unexpected exception
java.util.concurrent.ExecutionException: org.jenkinsci.remoting.protocol.impl.ConnectionRefusalException: Connection closed before acknowledgement sent
at org.jenkinsci.remoting.util.SettableFuture.get(SettableFuture.java:223)
at hudson.remoting.Engine.innerRun(Engine.java:594)
at hudson.remoting.Engine.run(Engine.java:455)
Caused by: org.jenkinsci.remoting.protocol.impl.ConnectionRefusalException: Connection closed before acknowledgement sent
at org.jenkinsci.remoting.protocol.impl.AckFilterLayer.onRecvClosed(AckFilterLayer.java:280)
at org.jenkinsci.remoting.protocol.FilterLayer.abort(FilterLayer.java:164)
at org.jenkinsci.remoting.protocol.impl.AckFilterLayer.abort(AckFilterLayer.java:130)
at org.jenkinsci.remoting.protocol.impl.AckFilterLayer.onRecv(AckFilterLayer.java:258)
at org.jenkinsci.remoting.protocol.ProtocolStack$Ptr.onRecv(ProtocolStack.java:669)
at org.jenkinsci.remoting.protocol.NetworkLayer.onRead(NetworkLayer.java:136)
at org.jenkinsci.remoting.protocol.impl.BIONetworkLayer.access$2200(BIONetworkLayer.java:48)
at org.jenkinsci.remoting.protocol.impl.BIONetworkLayer$Reader.run(BIONetworkLayer.java:283)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at hudson.remoting.Engine$1$1.run(Engine.java:98)
at java.lang.Thread.run(Unknown Source)

Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener status
INFO: Connecting to proxy.com:3698
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener status
INFO: Server reports protocol JNLP4-plaintext not supported, skipping
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener status
INFO: Server reports protocol JNLP3-connect not supported, skipping
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener status
INFO: Server reports protocol JNLP2-connect not supported, skipping
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener status
INFO: Server reports protocol JNLP-connect not supported, skipping
Jun 20, 2018 9:33:23 AM hudson.remoting.jnlp.Main$CuiListener error
SEVERE: The server rejected the connection: None of the protocols were accepted
java.lang.Exception: The server rejected the connection: None of the protocols were accepted
at hudson.remoting.Engine.onConnectionRejected(Engine.java:655)
at hudson.remoting.Engine.innerRun(Engine.java:619)
at hudson.remoting.Engine.run(Engine.java:455)

[KostyaSha]

It may be related to remoting. Even via proxy connection slave (remoting) gets list of master address and tries to connect firstly directly, then fails jenkinsci/remoting#275 Try block output connections to master address with ICMP REJECT.

[janisBerz]

We have managed to fix our proxy to relay TCP requests