On 6/3/2014 6:18 AM, Martin de Vries wrote: > I have two questions about upgrading Solr: > > - We upgrade Solr often, to match the latest version. We have a number > of servers in a Solrcloud and prefer to upgrade one or two servers first > and upgrade the other server a few weeks later when we are sure > everything is stable. Is this the recommended way? Can Solr run > different versions next to each other in a cloud?
Solr is usually able to have slightly different versions working together, but I don't know that I would recommend running for a few weeks in that configuration. In the context of SolrCloud, sometimes changes to the data structures in zookeeper are required, which likely will not work with a previous release. If you do find that they will work together, you can continue to do what you've been doing ... but you do need to be on the lookout for clusterstate format changes and possible interoperability bugs in the previous release. > - Do we need to adjust the luceneMatchVersion with every upgrade and do > we need a reindex after every upgrade? (it takes a lot of time to > reindex all cores) This is always recommended, but you can leave luceneMatchVersion alone and run with your existing index until such time as you are ready to re-index. Note that as soon as you index anything at all (or optimize your index), at least part of your index may be in a new index format, so going back to the previous version with the existing index may not be possible. Thanks, Shawn
