[JENKINS-23110] additional ssh command before ssh command that starts agent.jar results in StreamCorruptedException: invalid stream header: 090CACED

[jenkins-infra-bot]

I am using the option for creating slaves through command executed on master.

This is the error:

<===[JENKINS REMOTING CAPACITY]===>Exception in thread "main" java.io.StreamCorruptedException: invalid stream header: 090CACED
	at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:804)
	at java.io.ObjectInputStream.(ObjectInputStream.java:299)
	at hudson.remoting.ObjectInputStreamEx.(ObjectInputStreamEx.java:40)
	at hudson.remoting.ChannelBuilder.makeTransport(ChannelBuilder.java:259)
	at hudson.remoting.ChannelBuilder.negotiate(ChannelBuilder.java:220)
	at hudson.remoting.ChannelBuilder.build(ChannelBuilder.java:149)
	at hudson.remoting.Launcher.main(Launcher.java:507)
	at hudson.remoting.Launcher.runWithStdinStdout(Launcher.java:457)
	at hudson.remoting.Launcher.run(Launcher.java:238)
	at hudson.remoting.Launcher.main(Launcher.java:192)

ERROR: Unexpected error in launching a slave. This is probably a bug in Jenkins
hudson.remoting.RequestAbortedException: hudson.remoting.RequestAbortedException: java.io.IOException: Unexpected EOF
	at hudson.remoting.RequestAbortedException.wrapForRethrow(RequestAbortedException.java:41)
	at hudson.remoting.RequestAbortedException.wrapForRethrow(RequestAbortedException.java:34)
	at hudson.remoting.Request.call(Request.java:174)
	at hudson.remoting.Channel.call(Channel.java:739)
	at hudson.slaves.SlaveComputer.setChannel(SlaveComputer.java:443)
	at hudson.slaves.SlaveComputer.setChannel(SlaveComputer.java:339)
	at hudson.slaves.CommandLauncher.launch(CommandLauncher.java:122)
	at hudson.slaves.SlaveComputer$1.call(SlaveComputer.java:222)
	at jenkins.util.ContextResettingExecutorService$2.call(ContextResettingExecutorService.java:46)
	at java.util.concurrent.FutureTask.run(FutureTask.java:262)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:744)
ERROR: Connection terminated
java.io.IOException: Unexpected EOF
	at hudson.remoting.ChunkedInputStream.readUntilBreak(ChunkedInputStream.java:90)
	at hudson.remoting.ChunkedCommandTransport.readBlock(ChunkedCommandTransport.java:33)
	at hudson.remoting.AbstractSynchronousByteArrayCommandTransport.read(AbstractSynchronousByteArrayCommandTransport.java:34)
	at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:48)
Caused by: hudson.remoting.RequestAbortedException: java.io.IOException: Unexpected EOF
	at hudson.remoting.Request.abort(Request.java:299)
	at hudson.remoting.Channel.terminate(Channel.java:802)
	at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:69)
Caused by: java.io.IOException: Unexpected EOF
	at hudson.remoting.ChunkedInputStream.readUntilBreak(ChunkedInputStream.java:90)
	at hudson.remoting.ChunkedCommandTransport.readBlock(ChunkedCommandTransport.java:33)
	at hudson.remoting.AbstractSynchronousByteArrayCommandTransport.read(AbstractSynchronousByteArrayCommandTransport.java:34)
	at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:48)

I have captured (with a `tee` command) this output sent by the slave:

<===[JENKINS REMOTING CAPACITY]===>rO0ABXNyABpodWRzb24ucmVtb3RpbmcuQ2FwYWJpbGl0eQAAAAAAAAABAgABSgAEbWFza3hwAAAAAAAAAP4=

I have tried slave options like -text and definition of encoding without success.
My integration with Jenkins has come to a dead end

---

Originally reported by gdm85, imported from: additional ssh command before ssh command that starts agent.jar results in StreamCorruptedException: invalid stream header: 090CACED

• status: Open
• priority: Major
• component(s): command-launcher-plugin
• resolution: Unresolved
• votes: 1
• watchers: 5
• imported: 20251215-193512

Raw content of original issue

I am using the option for creating slaves through command executed on master.

This is the error:

<===[JENKINS REMOTING CAPACITY]===>Exception in thread "main" java.io.StreamCorruptedException: invalid stream header: 090CACED
	at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:804)
	at java.io.ObjectInputStream.<init>(ObjectInputStream.java:299)
	at hudson.remoting.ObjectInputStreamEx.<init>(ObjectInputStreamEx.java:40)
	at hudson.remoting.ChannelBuilder.makeTransport(ChannelBuilder.java:259)
	at hudson.remoting.ChannelBuilder.negotiate(ChannelBuilder.java:220)
	at hudson.remoting.ChannelBuilder.build(ChannelBuilder.java:149)
	at hudson.remoting.Launcher.main(Launcher.java:507)
	at hudson.remoting.Launcher.runWithStdinStdout(Launcher.java:457)
	at hudson.remoting.Launcher.run(Launcher.java:238)
	at hudson.remoting.Launcher.main(Launcher.java:192)

ERROR: Unexpected error in launching a slave. This is probably a bug in Jenkins
hudson.remoting.RequestAbortedException: hudson.remoting.RequestAbortedException: java.io.IOException: Unexpected EOF
	at hudson.remoting.RequestAbortedException.wrapForRethrow(RequestAbortedException.java:41)
	at hudson.remoting.RequestAbortedException.wrapForRethrow(RequestAbortedException.java:34)
	at hudson.remoting.Request.call(Request.java:174)
	at hudson.remoting.Channel.call(Channel.java:739)
	at hudson.slaves.SlaveComputer.setChannel(SlaveComputer.java:443)
	at hudson.slaves.SlaveComputer.setChannel(SlaveComputer.java:339)
	at hudson.slaves.CommandLauncher.launch(CommandLauncher.java:122)
	at hudson.slaves.SlaveComputer$1.call(SlaveComputer.java:222)
	at jenkins.util.ContextResettingExecutorService$2.call(ContextResettingExecutorService.java:46)
	at java.util.concurrent.FutureTask.run(FutureTask.java:262)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:744)
ERROR: Connection terminated
java.io.IOException: Unexpected EOF
	at hudson.remoting.ChunkedInputStream.readUntilBreak(ChunkedInputStream.java:90)
	at hudson.remoting.ChunkedCommandTransport.readBlock(ChunkedCommandTransport.java:33)
	at hudson.remoting.AbstractSynchronousByteArrayCommandTransport.read(AbstractSynchronousByteArrayCommandTransport.java:34)
	at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:48)
Caused by: hudson.remoting.RequestAbortedException: java.io.IOException: Unexpected EOF
	at hudson.remoting.Request.abort(Request.java:299)
	at hudson.remoting.Channel.terminate(Channel.java:802)
	at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:69)
Caused by: java.io.IOException: Unexpected EOF
	at hudson.remoting.ChunkedInputStream.readUntilBreak(ChunkedInputStream.java:90)
	at hudson.remoting.ChunkedCommandTransport.readBlock(ChunkedCommandTransport.java:33)
	at hudson.remoting.AbstractSynchronousByteArrayCommandTransport.read(AbstractSynchronousByteArrayCommandTransport.java:34)
	at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:48)


I have captured (with a `tee` command) this output sent by the slave:

<===[JENKINS REMOTING CAPACITY]===>rO0ABXNyABpodWRzb24ucmVtb3RpbmcuQ2FwYWJpbGl0eQAAAAAAAAABAgABSgAEbWFza3hwAAAAAAAAAP4=


I have tried slave options like -text and definition of encoding without success.
My integration with Jenkins has come to a dead end

• environment: Jenkins 1.563 running with OpenJDK 7



[jenkins-infra-bot]

ben_poole_aerian:

• Original comment link
• Raw content of original comment:

  I'm also experiencing this issue, was there any movement on it? Or a workaround?
  
  Thanks
  

I'm also experiencing this issue, was there any movement on it? Or a workaround?

Thanks

[jenkins-infra-bot]

t_herzke_2017:

• Original comment link
• Raw content of original comment:

  Details what the command on the server actually does to to launch the slave are missing from the report. I suppose it is a shell script that does something like
  
  
  
  ssh remote "rm -f /tmp/somefile"
  ssh remote "java -jar slave.jar" 
  
   In this case, the first ssh command consumes some bytes from the stdin for buffering purposes even if the remote command does not actually read stdin. The communication stram with the slave.jar, then, starts somewhere in the middle.
  See also the "Custom launcher" section at https://wiki.jenkins-ci.org/display/JENKINS/Remoting+issue .
  Suggestion to close this issue.
  

Details what the command on the server actually does to to launch the slave are missing from the report. I suppose it is a shell script that does something like

ssh remote "rm -f /tmp/somefile"
ssh remote "java -jar slave.jar" 

In this case, the first ssh command consumes some bytes from the stdin for buffering purposes even if the remote command does not actually read stdin. The communication stram with the slave.jar, then, starts somewhere in the middle.

See also the "Custom launcher" section at https://wiki.jenkins-ci.org/display/JENKINS/Remoting+issue .

Suggestion to close this issue.

[jenkins-infra-bot]

jsoref:

• Original comment link
• Raw content of original comment:

  I'd suggest improving the error message (and I'll provide a patch).
  
  Currently the error says:
  
  ERROR: Unexpected error in launching a slave. This is probably a bug in Jenkins
  
  
  A better message would say something like:
  
  ERROR: Failed to properly communicate with agent. This could be because a program (especially an additional ssh command before the one used to start agent.jar) consumed input which was destined for the agent. -- Otherwise, this could be a bug in Jenkins.
  
  Beyond that, it seems to me like the Jenkins server side should be able to wait for the agent's hello world message and only start sending bytes upon receiving that. Presumably that would fix the problem here.
  (FWIW, I just hit this today running 2.97.)
  

I'd suggest improving the error message (and I'll provide a patch).

Currently the error says:

ERROR: Unexpected error in launching a slave. This is probably a bug in Jenkins

A better message would say something like:

ERROR: Failed to properly communicate with agent. This could be because a program (especially an additional ssh command before the one used to start agent.jar) consumed input which was destined for the agent. -- Otherwise, this could be a bug in Jenkins.

Beyond that, it seems to me like the Jenkins server side should be able to wait for the agent's hello world message and only start sending bytes upon receiving that. Presumably that would fix the problem here.

(FWIW, I just hit this today running 2.97.)

[jenkins-infra-bot]

[Original relates_to from Jira: JENKINS-8856]

[jenkins-infra-bot]

[Original relates_to from Jira: JENKINS-13091]