the build fails with 
16:21:36 FATAL: command execution failed
16:24:49 java.io.EOFException
16:24:49  at java.base/java.io.ObjectInputStream$PeekInputStream.readFully(ObjectInputStream.java:2905)
16:24:49  at java.base/java.io.ObjectInputStream$BlockDataInputStream.readShort(ObjectInputStream.java:3400)
16:24:49  at java.base/java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:936)
16:24:49  at java.base/java.io.ObjectInputStream.<init>(ObjectInputStream.java:379)
16:24:49  at hudson.remoting.ObjectInputStreamEx.<init>(ObjectInputStreamEx.java:49)
16:24:49  at hudson.remoting.Command.readFrom(Command.java:142)
16:24:49  at hudson.remoting.Command.readFrom(Command.java:128)
16:24:49  at hudson.remoting.AbstractSynchronousByteArrayCommandTransport.read(AbstractSynchronousByteArrayCommandTransport.java:35)
16:24:49  at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:61)
16:24:49 Caused: java.io.IOException: Unexpected termination of the channel
16:24:49  at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:75)
16:24:49 Caused: java.io.IOException: Backing channel 'mhub-linux9' is disconnected.
16:24:49  at hudson.remoting.RemoteInvocationHandler.channelOrFail(RemoteInvocationHandler.java:215)
16:24:49  at hudson.remoting.RemoteInvocationHandler.invoke(RemoteInvocationHandler.java:285)
16:24:49  at com.sun.proxy.$Proxy105.isAlive(Unknown Source)
16:24:49  at hudson.Launcher$RemoteLauncher$ProcImpl.isAlive(Launcher.java:1215)
16:24:49  at hudson.Launcher$RemoteLauncher$ProcImpl.join(Launcher.java:1207)
16:24:49  at hudson.tasks.CommandInterpreter.join(CommandInterpreter.java:195)
16:24:49  at hudson.tasks.CommandInterpreter.perform(CommandInterpreter.java:145)
16:24:49  at hudson.tasks.CommandInterpreter.perform(CommandInterpreter.java:92)
16:24:49  at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:20)
16:24:49  at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:814)
16:24:49  at hudson.model.Build$BuildExecution.build(Build.java:199)
16:24:49  at hudson.model.Build$BuildExecution.doRun(Build.java:164)
16:24:49  at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:522)
16:24:49  at hudson.model.Run.execute(Run.java:1896)
16:24:49  at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:44)
16:24:49  at hudson.model.ResourceController.execute(ResourceController.java:101)
16:24:49  at hudson.model.Executor.run(Executor.java:442)
16:24:49 FATAL: Unable to delete script file /tmp/jenkins15763002140024398353.sh
16:24:49 java.io.EOFException
16:24:49  at java.base/java.io.ObjectInputStream$PeekInputStream.readFully(ObjectInputStream.java:2905)
16:24:49  at java.base/java.io.ObjectInputStream$BlockDataInputStream.readShort(ObjectInputStream.java:3400)
16:24:49  at java.base/java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:936)
16:24:49  at java.base/java.io.ObjectInputStream.<init>(ObjectInputStream.java:379)
16:24:49  at hudson.remoting.ObjectInputStreamEx.<init>(ObjectInputStreamEx.java:49)
16:24:49  at hudson.remoting.Command.readFrom(Command.java:142)
16:24:49  at hudson.remoting.Command.readFrom(Command.java:128)
16:24:49  at hudson.remoting.AbstractSynchronousByteArrayCommandTransport.read(AbstractSynchronousByteArrayCommandTransport.java:35)
16:24:49  at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:61)
16:24:49 Caused: java.io.IOException: Unexpected termination of the channel
16:24:49  at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:75)
16:24:49 Caused: hudson.remoting.ChannelClosedException: Channel "hudson.remoting.Channel@50af1e95:mhub-linux9": Remote call on mhub-linux9 failed. The channel is closing down or has closed down