Migrating to Jenkins 2.1- AJP support is removed in Winstone 3.0 due to Jetty 9 not supporting AJP

Question

I am moving from Jenkins 1.6.x installation to 2.x. Following error prevents Jenkins from starting

Jul 02, 2016 12:51:42 PM org.eclipse.jetty.util.log.JavaUtilLog warn
WARNING: Empty contextPath
Jul 02, 2016 12:51:42 PM winstone.Logger logInternal
INFO: Winstone shutdown successfully
Jul 02, 2016 12:51:42 PM winstone.Logger logInternal
SEVERE: Container startup failed
java.io.IOException: Failed to start a listener: winstone.Ajp13ConnectorFactory
        at winstone.Launcher.spawnListener(Launcher.java:207)
        at winstone.Launcher.<init>(Launcher.java:148)
        at winstone.Launcher.main(Launcher.java:352)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:497)
        at Main._main(Main.java:246)
        at Main.main(Main.java:91)
Caused by: java.lang.UnsupportedOperationException: AJP support is removed in Winstone 3.0 due to Jetty 9 not supporting AJP. For reverse proxying, please use HTTP instead of AJP.
        at winstone.Ajp13ConnectorFactory.start(Ajp13ConnectorFactory.java:31)
        at winstone.Launcher.spawnListener(Launcher.java:205)
        ... 8 more

Running from: /usr/lib/jenkins/jenkins.war

How can I bring it up?

Answer 1

This is in the Jenkins 2.0 Overview:

Jenkins 2 no longer supports AJP with the embedded Winstone-Jetty container

The solution is to disable AJP. To quote the bugtracker:

Setting JENKINS_AJP_PORT="-1" in /etc/sysconfig/jenkins solved problem