Unable to create solr core

Question

I have a solr 5.2.1 instance and I want to create a new core named production. I had several issues with access rights which got solved, but the following exception is totally unclear to me. Help is appreciated.

org.apache.solr.common.SolrException: Error CREATEing SolrCore 'production': Unable to create core [production] Caused by: solr.JsonUpdateRequestHandler
    at org.apache.solr.handler.admin.CoreAdminHandler.handleCreateAction(CoreAdminHandler.java:661)
    at org.apache.solr.handler.admin.CoreAdminHandler.handleRequestInternal(CoreAdminHandler.java:213)
    at org.apache.solr.handler.admin.CoreAdminHandler.handleRequestBody(CoreAdminHandler.java:193)
    at org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:143)
    at org.apache.solr.servlet.HttpSolrCall.handleAdminRequest(HttpSolrCall.java:660)
    at org.apache.solr.servlet.HttpSolrCall.call(HttpSolrCall.java:431)
    at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:227)
    at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:196)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)
    at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
    at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:577)
    at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
    at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127)
    at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
    at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
    at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
    at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:215)
    at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:110)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.Server.handle(Server.java:497)
    at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:310)
    at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257)
    at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)
    at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)
    at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.solr.common.SolrException: Unable to create core [production]
    at org.apache.solr.core.CoreContainer.create(CoreContainer.java:651)
    at org.apache.solr.core.CoreContainer.create(CoreContainer.java:611)
    at org.apache.solr.handler.admin.CoreAdminHandler.handleCreateAction(CoreAdminHandler.java:628)
    ... 27 more
Caused by: org.apache.solr.common.SolrException: Error loading class 'solr.JsonUpdateRequestHandler'
    at org.apache.solr.core.SolrCore.<init>(SolrCore.java:815)
    at org.apache.solr.core.SolrCore.<init>(SolrCore.java:658)
    at org.apache.solr.core.CoreContainer.create(CoreContainer.java:637)
    ... 29 more
Caused by: org.apache.solr.common.SolrException: Error loading class 'solr.JsonUpdateRequestHandler'
    at org.apache.solr.core.SolrResourceLoader.findClass(SolrResourceLoader.java:491)
    at org.apache.solr.core.SolrResourceLoader.findClass(SolrResourceLoader.java:422)
    at org.apache.solr.core.SolrCore.createInstance(SolrCore.java:566)
    at org.apache.solr.core.PluginBag.createPlugin(PluginBag.java:122)
    at org.apache.solr.core.PluginBag.init(PluginBag.java:217)
    at org.apache.solr.core.RequestHandlers.initHandlersFromConfig(RequestHandlers.java:130)
    at org.apache.solr.core.SolrCore.<init>(SolrCore.java:768)
    ... 31 more
Caused by: java.lang.ClassNotFoundException: solr.JsonUpdateRequestHandler
    at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
    at java.net.FactoryURLClassLoader.loadClass(URLClassLoader.java:793)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:278)
    at org.apache.solr.core.SolrResourceLoader.findClass(SolrResourceLoader.java:475)

Answer 1

It seems that you are using an old version of solrconfig.xml. Class JsonUpdateRequestHandler was deprecated in latest Solr 4.x versions and was removed from Solr 5.x. You should use UpdateRequestHandler instead of it and update your solrconfig.xml according to your Solr version.