For that, we provide an index upgrade tool with 6.0, like we did in 5.0. On Tue, Feb 23, 2016 at 10:41 AM, Mike Drob <md...@apache.org> wrote:
> A 5.x Solr could have indices that are still in a 4.x format, right? That > would be one point where it's not "fully back compatible." > > On Tue, Feb 23, 2016 at 12:27 PM, Shai Erera <ser...@gmail.com> wrote: > >> Wait, what do you mean by Lucene not supporting back-compat? Lucene 6.0 >> will be able to read Lucene 5.0 indexes. The only thing that we don't >> guarantee support for is API, which isn't the case here. >> >> So what's in 6.0 that can't read a 5.x Solr. It can't be the index format >> since that's supported by Lucene. Is it the ZK format? If so, should we try >> to "version" it so that a 6.0 code can read a 5.x version? Is it something >> else / additionally? >> >> Shai >> >> On Tue, Feb 23, 2016 at 7:06 PM Mark Miller <markrmil...@gmail.com> >> wrote: >> >>> Yes, we are allowed wide berth to break backcompat across major versions >>> and we cannot support rolling updates for the same reason Lucene stopped >>> trying to do full back compat across major versions. Without, we can't >>> properly innovate in the code or fix past mistakes and would also burn lots >>> of cycles we don't have on crazy, "sophisticated" back compat layers. >>> >>> We don't even really support rolling updates between major versions. We >>> make a simple best effort. Until we have tests, it's going to be a shaky >>> affair. There is a JIRA open now working on some testing I believe. >>> >>> - Mark >>> >>> On Tue, Feb 23, 2016 at 11:29 AM Shai Erera <ser...@gmail.com> wrote: >>> >>>> Hi >>>> >>>> I read in few emails/issue comments that rolling upgrades from 5.x to >>>> 6.0 isn't supported. Is it really the case? Does it mean that anyone who >>>> has a 5.x Solr cluster *must* incur down time when upgrading to 6.0? >>>> >>>> If this is really the case, can someone list the known issues/reasons >>>> for that?Can we do something about it, e.g. in a subsequent 5.6 release >>>> that will allow rolling upgrades (like the 5.4.1 fix that allowed rolling >>>> upgrades from pre-5.4 to 5.4)? >>>> >>>> I feel it's odd (and may not be taken well) if we force users to take >>>> down their entire cluster if they want to upgrade to 6.0. Definitely feels >>>> like it will also slow down 6.0 adoption. >>>> >>>> And if nothing can be done, what's the recommended way then to upgrade >>>> to 6.0? >>>> >>>> Shai >>>> >>> -- >>> - Mark >>> about.me/markrmiller >>> >> > -- Anshum Gupta
