bq: ...whether it's OK to just copy the data files between 4.3 and 6.x NOT ok. Solr (well, Lucene really) guarantees to read _one_ major version behind. So a Solr 5x will read a solr 4x. But a Solr 6x is not guaranteed at all to read a 4x. And in fact removing back-compat complexification is one of the benefits of moving to a new major version.
You can use the 5x IndexUpgraderTool to migrate from 4x->5x, then run 6x over the upgraded index. All that said, I completely agree with John's advice to re-index entirely from scratch if at all possible. ********** It's perfectly possible to run with a single Zookeeper. The quorum formula is N/2 + 1. If you only have 1 ZK node, then 1 represents quorum. It's just not advisable. Zk is responsible for presenting the cluster topology to the entire set of Solr instances, you want it to be robust so 3 is the recommended minimum. BTW, It's quite rare to need more than that unless you're at pretty massive scale (hundreds of Solr instances and/or collections), and even in these cases it's usually best to use Observers.... FWIW, Erick On Tue, Oct 18, 2016 at 2:28 PM, John Bickerstaff <j...@johnbickerstaff.com> wrote: > For what it's worth, (and it may not work for your situation) I decided not > to upgrade, but to "upgrade by replacing". In other words, I just > installed 6.x and because I had set up my configs for "include" I didn't > have to worry about what would be different about the "new" solrconfig.xml > and the managed_schema file. Instead, I was able to use a copy from one of > the sample projects and add my "included" configs. > > Then, after creating the same collection structure in 6.x that I had in my > 5.x instances, I just re-indexed everything into the new 6.x Solr. > > The big deal (probably) is whether it will cost you days to re-index and > whether you have the resources to do that. > > I don't know if the index remained the same because I didn't have to > trouble myself with that due to the replacement. I'm sure others on the > list can tell us whether it's OK to just copy the data files between 4.3 > and 6.x (I'd guess not...) > > By the way - unless I misunderstand the Zookeeper docs, you can't get away > with any less than 3 Zookeeper nodes. So keep that in mind. > > I have my rough notes about what I did available online. You can go here > for the link... > > https://www.linkedin.com/pulse/actual-solrcloud-vms-zookeeper-nodes-john-bickerstaff > > > > > > > On Tue, Oct 18, 2016 at 11:28 AM, sputul <sputu...@gmail.com> wrote: > >> We are using Solr 4.3, sing Zoopeeker on development manage Solr Cloud >> having >> one or two nodes. Will it be easier to migrate to Solr 5 first or should I >> migrate to Solr 6 directly? I see Core definition has changed. Anything >> else >> worth noting? >> >> The goal is to also use HTTPS perhaps after everything works in my local >> environment using Single Zookeeper and a one or more Solr Nodes. Thanks. >> >> >> >> -- >> View this message in context: http://lucene.472066.n3. >> nabble.com/Migration-from-Solr-4-tp4301788.html >> Sent from the Solr - User mailing list archive at Nabble.com. >>
