While playing around with one of my development SOLR installations (this time under Windows), I suddenly got a weird error message when feeding data to one of the fresh cores.
SEVERE: java.lang.RuntimeException: java.io.FileNotFoundException: no segments* file found in org.apache.lucene.store.SimpleFSDirectory@C:\temp\solr\*\data\index: files:
Taking a look at the contents of the index\ directory, it was in fact empty. Seems weird, but my initial guess was that Lucene / SOLR would treat this as a new installation and create the files.
Turns out the issue is that it won’t – as long as the index directory exists, Lucene / SOLR goes looking for the segment files.
Thanks to an old post to the solr-dev list by Yonik, the easiest fix is to simply delete the index directory and restart your applet container (Tomcat in this case).