On 10/2/2013 1:08 AM, subacini Arunkumar wrote: > We are planning to upgrade from Solr 3.5 to Solr 4.x version. Appreciate if > you can provide any pointers/documentation on step by step by changes. > > Also, the reason for upgrading is to use Solr join [not solr cloud or any > other feature]. So which version is better Solr 4.0 or higher version > considering the changes to be minimal during upgradation.
When it comes to open source software, it's usually best to run the latest version. If there's a major problem with a particular release, it will be *QUICKLY* followed by a point release to fix those problems, or a workaround will be prominently posted. When new releases happen after that, it's best to start testing with it right away and upgrade your production install as soon as you feel comfortable with it. If the latest version just came out, you might want to start with one version back, but plan on upgrading to the latest version quickly afterwards. The 4.0.0 release came out on October 12, 2012. That's one year ago. There have been six releases since then, and a seventh (4.5.0) is days from announcement. Every release comes with a CHANGES.txt file, where individual issues are listed and important upgrade notes are given. It's also a good idea to compare the example config/schema from the version you're running to the example config/schema in the new version in order to see what has changed there, for clues about how you might want to change your own configuration. When upgrading major releases, it is probably a good idea to start with the example config/schema and make changes until it does what you need. It's also a *very* good idea to build up a complete system in a dev environment so you can run extensive tests without making any changes to your production setup. Finally, stay subscribed to this mailing list, the user list. Typical problems and bugs are very likely to be discussed here. If you want to get down and dirty and don't mind a lot of email traffic, you can also join the dev list. Thanks, Shawn
