My Jenkins install was whining at me to upgrade to the newest release (2.57) for security reasons. I finally relented, and updated the jenkins.war file only to be greeted with this wonderful error:
HTTP ERROR: 503
Problem accessing /. Reason:
Service UnavailableNot terribly informative. My first Google perusal revealed that it was probably an error with Jetty, and so I checked jetty configurations. No luck there there though.
I looked at the Jenkins log (/var/log/jenkins/jenkins.log), and found this:
WARNING: Failed to delete the temporary Winstone file /tmp/winstone/jenkins.war
May 01, 2017 12:29:43 PM org.eclipse.jetty.util.log.JavaUtilLog info
INFO: Logging initialized @923ms
May 01, 2017 12:29:43 PM winstone.Logger logInternal
INFO: Beginning extraction from war file
May 01, 2017 12:29:43 PM org.eclipse.jetty.util.log.JavaUtilLog warn
WARNING: Empty contextPath
May 01, 2017 12:29:43 PM org.eclipse.jetty.util.log.JavaUtilLog info
INFO: jetty-9.2.z-SNAPSHOT
May 01, 2017 12:29:44 PM org.eclipse.jetty.util.log.JavaUtilLog info
INFO: NO JSP Support for /, did not find org.eclipse.jetty.jsp.JettyJspServlet
May 01, 2017 12:29:44 PM org.eclipse.jetty.util.log.JavaUtilLog warn
WARNING: Failed startup of context w.@18d4479b{/,file:/var/cache/jenkins/war/,STARTING}{/var/cache/jenkins/war}
java.lang.reflect.InvocationTargetExceptionLooks like I am having trouble writing/removing files. So, I check permissions and users, but nothing looks out of the ordinary there.
I also use my Google-fu to see if I can get any clue on the last warning there. The only similar issues I can find are related to missing font-packs. That doesn’t make too much sense, but I try it any way. No avail.
Finally, I tried upgrading my Java install to 1.8 from 1.7. I looked through the Jenkins release notes, and I didn’t see anything overtly saying that Java 8 is the new requirement, but I did see some notes about Java 9 being supported, and Java 7 being the minimum for slaves.
I followed the instructions here to install Java 8, and what do you know? Success! So there you go. If you upgrade your Jenkins and see this error, try upgrading to Java 8!