Issue
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I would like to launch inbound agents to connect to a Jenkins controller
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When launching inbound agents, the launch fails with arguments passing errors such as
"<option>" is not a valid option,"<option>" is requiredoroption "<option1>" cannot be used with the option(s) <list of options>
Environment
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CloudBees CI (CloudBees Core) on modern cloud platforms - Managed controller
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CloudBees CI (CloudBees Core) on modern cloud platforms - Operations Center
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CloudBees CI (CloudBees Core) on traditional platforms - Client controller
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CloudBees CI (CloudBees Core) on traditional platforms - Operations Center
Resolution
There are mainly 2 recommended ways of starting an inbound agent with Java, and depending on the approach chosen, different options and arguments can be used:
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The more common and simplistic approach is by downloading a JNLP file and using the
Launcher, typically:java -jar agent.jar -jnlpUrl <jnlpUrl> .... -
The raw approach, by executing the Remoting
Mainentrypoint, typically:java -cp agent.jar hudson.remoting.jnlp.Main -headless ...
There is no recommendation whether to use one or another. The raw approach allow more fine-grained configuration.
Launcher / JNLP File
The most common way, that is also advertised in the Node page, is by using the remoting Launcher and pass the URL of the JNLP File:
java -jar agent.jar -jnlpUrl "${JENKINS_URL}"/computer/"${AGENT_NAME}"/jenkins-agent.jnlp ....
This command retrieve the jenkins-agent.jnlp file at "${JENKINS_URL}"/computer/"${AGENT_NAME}"/jenkins-agent.jnlp via HTTP/S. It is an XML file and can be read with cat or a text editor. That file contains the options and arguments that will be passed to the hudson.remoting.jnlp.Main class of remoting to start the agent (like the raw approach does).
Use java -jar agent.jar -help to see the options.
Raw approach with hudson.remoting.jnlp.Main
Another way, not advertised in the Node page, is to add agent.jar to the CLASSPATH and execute the hudson.remoting.jnlp.Main directly:
java -cp agent.jar hudson.remoting.jnlp.Main ...
This method is a raw command to which you need to provide all necessary arguments. This is the method used in the Inbound Agent images such as jenkins/inbound-agent and cloudbees/cloudbees-core-agent to launch the agent.
Use java -cp agent.jar hudson.remoting.jnlp.Main -help to see the options.