: SEVERE: null:java.lang.IllegalAccessError: : class org.apache.lucene.codecs.lucene3x.PreFlexRWPostingsFormat cannot access : its superclass org.apache.lucene.codecs.lucene3x.Lucene3xPostingsFormat
that sounds like a classpath error. : Very strange, because some lines earlier in the logs I have: : : Oct 15, 2012 2:30:24 PM org.apache.solr.core.SolrConfig initLibs : INFO: Adding specified lib dirs to ClassLoader : Oct 15, 2012 2:30:24 PM org.apache.solr.core.SolrResourceLoader replaceClassLoader : INFO: Adding 'file:/srv/www/solr/solr-4.0.0/lib/lucene-core-4.0-SNAPSHOT.jar' to classloader ...and that looks like a mistake. based on that log line, you either have a copy of the lucene core jar in the implicit "lib" dir for your solr core, or you have an explicit <lib ... /> directive pointed somewhere that contains a copy of the lucene-core jar -- either way telling slr to load the lucene-core jar as a plugin. but lucene-core should not be loaded as a plugin. lucene-core is already in the solr.war, and should have been loaded long before SolrConfig started looking for plugin libraries. which means you probably have two copies of the lucene-core jar ... and if you have two copies of that jar, you probably have two copies of oher lucene jars. which begs the questions: * what is you solr home dir? (i'me guessing maybe it's "/srv/www/solr/solr-4.0.0/" ?) * why do you have a copy of lucene-core in /srv/www/solr/solr-4.0.0/lib ? * what <lib .. /> directives do you have in your solrconfig.xml and why? -Hoss
