On 5/10/2013 5:11 AM, Jan Høydahl wrote: > Hi, > > The fastest way to upgrade is to leave luceneMatchVersion as LUCENE_40. Then > you will not get any surprises wrt changed behavior for existing > functionality. but you will get all the bug fixes. You can test it out on > your dev box.
I've wondered if it would be possible to create a list on the wiki of how Solr behaves differently with each successive bump in luceneMatchVersion. That would be very helpful in helping people with their upgrades. > The first time Solr reads the existing index, it will be converted to 4.3 > format, so keep a backup in case you wish to downgrade again, since 4.0 will > not read this index. I'm not 100% sure if this auto conversion will > compressed stored fields for you or if you need a re-index for that. I'm not sure this is right. Solr should leave existing segments alone, but write new segments in the new format. An optimize would be required to upgrade the format of the whole index. Of course a full reindex after changing luceneMatchVersion is the recommended way to go, because that version number change might result in the indexing happening differently. One person on IRC had trouble with the compression in 4.2.1 not being enabled even when deleting the entire index directory and starting over, but the entire situation sounded like their upgrade was perhaps not complete, and I never could figure out what was happening. Thanks, Shawn