On 10/30/2017 2:45 PM, Dan Caulfield wrote: > Thanks Shawn, > I tried your recommended solution and delete the maxis_clickstream > directory. I got the same error when trying to recreate the collection. > Can you think of anything else to try?
I am pretty sure that this problem happens because the data/index directory for a core exists when Solr tries to create a core for the collection that it has been asked to create. The error messages I saw in your original email indicated that the only file present in each of the index directories at the time of the error was "write.lock". I'm pretty sure this could only happen if the index directory was already there when Solr tried to create the index, but contained zero files until Solr started the index creation. Before you issue the CREATE call via HTTP, are you doing any manual work on your HDFS filesystem? If so, you shouldn't do that. When running in cloud mode, Solr will create all of the files and directories it needs as part of the collection creation. I think it's a bug that Lucene/Solr refuses to create a new index when the index directory exists but contains no files. This has been the behavior for a VERY long time, and nobody has tried to fix it yet. When the index directory exists, *does* contain files, but not the critical files that Lucene expects, then that error would be the right thing to do. I found an existing issue for the problem with empty index directories and submitted a patch for the issue, but I haven't yet heard whether I accomplished the fix correctly: https://issues.apache.org/jira/browse/SOLR-8628 Thanks, Shawn
