Mark, I understand that we currently don't have any other promises :). I asked in case you happen to know that "oh yeah, in 6.0 we've changed ZK to refer to /solr_collections instead of /collections" (I wish it would be *that* trivial :)).
If you don't have a list that's fine. You just sounded really confident that 5.x -> 6.0 won't work, so I hoped you also can tell why. I think we should try to be back-compat here, i.e. that a 6.0 (or 7.0) can read a 5.0 (or 6.0) Solr. If ZK is our "format", then we should treat it as a thing we want to support. That's just my opinion though. Shai On Tue, Feb 23, 2016 at 8:46 PM Anshum Gupta <[email protected]> wrote: > 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 <[email protected]> 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 <[email protected]> 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 <[email protected]> >>> 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 <[email protected]> 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 >
