[xwiki-users] Diagnosing empty start page

22 Aug 2016

      Hi,

It's been a while since I've installed XWiki from scratch, and last time it was for Ubuntu 14 with 7.1.1. It looks like enough things have changed since then that I'm doing something wrong. I'd appreciate any help in diagnosing the problem.

This time I'm using Ubuntu 16.04.1 and Tomcat 8. I'm installing from the debian/Ubuntu xwiki-enterprise-tomcat8-pgsql package version 8.2.1, with Tomcat8 package 8.0.32-1ubuntu1.1. It's running (as before) via an AJP connector behind Apache2.

https://mysite/xwiki correctly redirects to https://mysite/xwiki/bin/view/Main/ so it looks like something is happening, but I'm getting an empty page. The following are the Catalina log entries (please excuse the length) from restarting tomcat onwards. My experience has been that one always gets some warnings, but my guess is that one or more of the following are resulting in pages failing to load.

22-Aug-2016 10:11:46.465 INFO [Thread-11] org.apache.coyote.AbstractProtocol.pause Pausing ProtocolHandler ["ajp-nio-8009"]
22-Aug-2016 10:11:46.471 INFO [Thread-11] org.apache.catalina.core.StandardService.stopInternal Stopping service Catalina
22-Aug-2016 10:11:46.536 SEVERE [Catalina-startStop-2] org.apache.catalina.core.ContainerBase.stopInternal A child container failed during stop
 java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to stop component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[]]
        at java.util.concurrent.FutureTask.report(java.base@9-internal/FutureTask.java:123)
        at java.util.concurrent.FutureTask.get(java.base@9-internal/FutureTask.java:193)
        at org.apache.catalina.core.ContainerBase.stopInternal(ContainerBase.java:972)
        at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:224)
        at org.apache.catalina.core.ContainerBase$StopChild.call(ContainerBase.java:1424)
        at org.apache.catalina.core.ContainerBase$StopChild.call(ContainerBase.java:1413)
        at java.util.concurrent.FutureTask.run(java.base@9-internal/FutureTask.java:266)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(java.base@9-internal/ThreadPoolExecutor.java:1158)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(java.base@9-internal/ThreadPoolExecutor.java:632)
        at java.lang.Thread.run(java.base@9-internal/Thread.java:804)
Caused by: org.apache.catalina.LifecycleException: Failed to stop component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[]]
        at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:228)
        ... 6 more
Caused by: org.apache.catalina.LifecycleException: Failed to stop component [WebappLoader[]]
        at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:228)
        at org.apache.catalina.core.StandardContext.stopInternal(StandardContext.java:5517)
        at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:224)
        ... 6 more
Caused by: java.lang.reflect.InaccessibleObjectException: Unable to make member of class sun.rmi.transport.Target accessible:  module java.rmi does not export sun.rmi.transport to unnamed module @4abdb505
        at sun.reflect.Reflection.throwInaccessibleObjectException(java.base@9-internal/Reflection.java:420)
        at java.lang.reflect.AccessibleObject.checkCanSetAccessible(java.base@9-internal/AccessibleObject.java:174)
        at java.lang.reflect.Field.checkCanSetAccessible(java.base@9-internal/Field.java:170)
        at java.lang.reflect.Field.setAccessible(java.base@9-internal/Field.java:164)
        at org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesRmiTargets(WebappClassLoaderBase.java:2234)
        at org.apache.catalina.loader.WebappClassLoaderBase.clearReferences(WebappClassLoaderBase.java:1553)
        at org.apache.catalina.loader.WebappClassLoaderBase.stop(WebappClassLoaderBase.java:1496)
        at org.apache.catalina.loader.WebappLoader.stopInternal(WebappLoader.java:446)
        at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:224)
        ... 8 more
22-Aug-2016 10:12:07.202 WARNING [main] org.apache.catalina.startup.ClassLoaderFactory.validateFile Problem with directory [/usr/share/tomcat8/common/classes], exists: [false], isDirectory: [false], canRead: [false]
22-Aug-2016 10:12:07.262 WARNING [main] org.apache.catalina.startup.ClassLoaderFactory.validateFile Problem with directory [/usr/share/tomcat8/common], exists: [false], isDirectory: [false], canRead: [false]
22-Aug-2016 10:12:07.271 WARNING [main] org.apache.catalina.startup.ClassLoaderFactory.validateFile Problem with directory [/usr/share/tomcat8/server/classes], exists: [false], isDirectory: [false], canRead: [false]
22-Aug-2016 10:12:07.277 WARNING [main] org.apache.catalina.startup.ClassLoaderFactory.validateFile Problem with directory [/usr/share/tomcat8/server], exists: [false], isDirectory: [false], canRead: [false]
22-Aug-2016 10:12:07.281 WARNING [main] org.apache.catalina.startup.ClassLoaderFactory.validateFile Problem with directory [/usr/share/tomcat8/shared/classes], exists: [false], isDirectory: [false], canRead: [false]
22-Aug-2016 10:12:07.285 WARNING [main] org.apache.catalina.startup.ClassLoaderFactory.validateFile Problem with directory [/usr/share/tomcat8/shared], exists: [false], isDirectory: [false], canRead: [false]
22-Aug-2016 10:12:08.760 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server version:        Apache Tomcat/8.0.32 (Ubuntu)
22-Aug-2016 10:12:08.763 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server built:          Jul 6 2016 11:49:29 UTC
22-Aug-2016 10:12:08.768 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server number:         8.0.32.0
22-Aug-2016 10:12:08.770 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log OS Name:               Linux
22-Aug-2016 10:12:08.772 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log OS Version:            4.4.0-28-generic
22-Aug-2016 10:12:08.772 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Architecture:          amd64
22-Aug-2016 10:12:08.776 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Java Home:             /usr/lib/jvm/java-9-openjdk-amd64
22-Aug-2016 10:12:08.779 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Version:           9-internal+0-2016-04-14-195246.buildd.src
22-Aug-2016 10:12:08.780 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Vendor:            Oracle Corporation
22-Aug-2016 10:12:08.781 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_BASE:         /var/lib/tomcat8
22-Aug-2016 10:12:08.784 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_HOME:         /usr/share/tomcat8
22-Aug-2016 10:12:08.798 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.config.file=/var/lib/tomcat8/conf/logging.properties
22-Aug-2016 10:12:08.801 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
22-Aug-2016 10:12:08.808 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.awt.headless=true
22-Aug-2016 10:12:08.812 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Xmx1024m
22-Aug-2016 10:12:08.812 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -XX:+UseConcMarkSweepGC
22-Aug-2016 10:12:08.813 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.base=/var/lib/tomcat8
22-Aug-2016 10:12:08.814 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.home=/usr/share/tomcat8
22-Aug-2016 10:12:08.814 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.io.tmpdir=/tmp/tomcat8-tomcat8-tmp
22-Aug-2016 10:12:08.823 SEVERE [main] org.apache.catalina.core.JreMemoryLeakPreventionListener.lifecycleEvent Failed to trigger creation of the GC Daemon thread during Tomcat start to prevent possible memory leaks. This is expected on non-Sun JVMs.
 java.lang.ClassNotFoundException: sun.misc.GC
        at java.net.URLClassLoader.findClass(java.base@9-internal/URLClassLoader.java:384)
        at java.lang.ClassLoader.loadClass(java.base@9-internal/ClassLoader.java:486)
        at java.lang.ClassLoader.loadClass(java.base@9-internal/ClassLoader.java:419)
        at java.lang.Class.forName0(java.base@9-internal/Native Method)
        at java.lang.Class.forName(java.base@9-internal/Class.java:294)
        at org.apache.catalina.core.JreMemoryLeakPreventionListener.lifecycleEvent(JreMemoryLeakPreventionListener.java:310)
        at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:95)
        at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
        at org.apache.catalina.util.LifecycleBase.setStateInternal(LifecycleBase.java:394)
        at org.apache.catalina.util.LifecycleBase.init(LifecycleBase.java:99)
        at org.apache.catalina.startup.Catalina.load(Catalina.java:580)
        at org.apache.catalina.startup.Catalina.load(Catalina.java:603)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(java.base@9-internal/Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(java.base@9-internal/NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(java.base@9-internal/DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(java.base@9-internal/Method.java:531)
        at org.apache.catalina.startup.Bootstrap.load(Bootstrap.java:310)
        at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:484)

22-Aug-2016 10:12:09.194 INFO [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["ajp-nio-8009"]
22-Aug-2016 10:12:09.241 INFO [main] org.apache.tomcat.util.net.NioSelectorPool.getSharedSelector Using a shared selector for servlet write/read
22-Aug-2016 10:12:09.256 INFO [main] org.apache.catalina.startup.Catalina.load Initialization processed in 1838 ms
22-Aug-2016 10:12:09.350 INFO [main] org.apache.catalina.core.StandardService.startInternal Starting service Catalina
22-Aug-2016 10:12:09.352 INFO [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Apache Tomcat/8.0.32 (Ubuntu)
22-Aug-2016 10:12:09.389 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDescriptor Deploying configuration descriptor /etc/tomcat8/Catalina/localhost/xwiki.xml
22-Aug-2016 10:12:09.525 WARNING [localhost-startStop-1] org.apache.catalina.startup.SetContextPropertiesRule.begin [SetContextPropertiesRule]{Context} Setting property 'allowLinking' to 'true' did not find a matching property.
22-Aug-2016 10:12:12.567 INFO [localhost-startStop-1] org.apache.catalina.loader.WebappLoader.buildClassPath Unknown loader jdk.internal.loader.ClassLoaders$AppClassLoader@5f150435 class jdk.internal.loader.ClassLoaders$AppClassLoader
22-Aug-2016 10:12:56.206 INFO [localhost-startStop-1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
22-Aug-2016 10:13:31.784 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDescriptor Deployment of configuration descriptor /etc/tomcat8/Catalina/localhost/xwiki.xml has finished in 82,375 ms
22-Aug-2016 10:13:31.791 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /var/lib/tomcat8/webapps/ROOT
22-Aug-2016 10:13:31.828 INFO [localhost-startStop-1] org.apache.catalina.loader.WebappLoader.buildClassPath Unknown loader jdk.internal.loader.ClassLoaders$AppClassLoader@5f150435 class jdk.internal.loader.ClassLoaders$AppClassLoader
22-Aug-2016 10:13:32.824 INFO [localhost-startStop-1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
22-Aug-2016 10:13:32.836 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /var/lib/tomcat8/webapps/ROOT has finished in 1,045 ms
22-Aug-2016 10:13:32.849 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["ajp-nio-8009"]
22-Aug-2016 10:13:32.884 INFO [main] org.apache.catalina.startup.Catalina.start Server startup in 83627 ms

Visiting the page in my browser then gets a blank page, and there are no further entries in the log. Can anyone advise what might be the next step in resolving things?

Thanks,

Bryn

[xwiki-users] Diagnosing empty start page

Bryn Jeffries