It’s variable. The policy is that we try very hard to maintain one major version back-compat. So generally, if you start with, say, 7x upgrading to 8x should be relatively straightforward. However, you will _not_ be able to upgrade from 7x to 9x, you must re-index everything from scratch.
The development process is this: - People work on “master”, the future 9.0 - most changes are back-ported to the current one-less-major-version, in this case 8x. Periodically (on no fixed schedule, but usually 3-4 times a year) a new 8x version is released. Some changes to master are not backported as they are major changes that would be difficult/impossible to backport. - at some point, especially when enough non-backported changes have accumulated, we decide to release 9.0 and everything bumps up one, i.e. master is the future 10.0, work is done there and backported to the stable 9x - In the current situation, where work is done on the future 9.0 and 8.x is the stable branch, there will be _no_ work done on 7x excepting egregious problems which at this point are pretty much exclusively security vulnerabilities. - As I said, it’s variable. I expect 9.0 to happen sometime in the first half of next year, but there are no solid plans for that, it’s just how I personally think things are shaping up. - Finally, the transition from the last release of a major version to the first release of a new major version is _usually_ not a huge deal. New major releases are free to remove deprecated methods and processes though, so that’s one thing to watch for. So in a nutshell, if you are starting a new project you have two choices: - use the latest 8.x. that’ll get you the longest period when fixes will be made to that branch, although development will taper off on that branch as 9.0 gets released. A variant here is to start with 8x, and if 9.0 gets released before go-live, try upgrading part way through the project. - If your time-frame is long enough, start with master (the future 9.0) which you’ll have to compile yourself, understanding that - it may be unstable - the timeframe for an official release is not fixed. > On Nov 6, 2019, at 1:00 AM, suyog joshi <suyogjos...@gmail.com> wrote: > > Hi Team, > > Can you please guide us on below queries for solr versions ? > > 1. Are there any major differences (for security, platform stability etc) > between current LTS and Stable Solr version ? > 2. How long a version remains in LTS before becoming EoL ? > 3. How frequently LTS version gets changed ? > 3. What will be the next LTS version for Solr(current is 7.7.x) ? > > > Kindly advice, you guidance will be really helpful for us to select correct > version in our infra. > > Regards, > Suyog Joshi > > > > -- > Sent from: https://lucene.472066.n3.nabble.com/Solr-User-f472068.html
