FWIW, one way that we have used to determine whether a collection is ready for upgrade is to run a command like
java -Xms512m -Xmx4g -cp lucene-core-8.5.2.jar -ea:org.apache.lucene... org.apache.lucene.index.CheckIndex /your/path/here/snapshot.211006-054002/snapshot.shard1 This will balk if the data was created under Solr6, but is happy enough with Solr7 (although this does not check for such things as deprecated data types) I would still be interested in the answer to your original question, so that I can confirm that all our data will be ready for Solr9 upgrade (preferably without having to wait for lucene-core-9.0.0.jar to come into existence). We do a complete reindex when we upgrade (but I want to check that no one skipped that step) -----Original Message----- From: Dave <hastings.recurs...@gmail.com> Sent: Wednesday, October 06, 2021 9:11 AM To: users@solr.apache.org Cc: Jason Carter <ja...@newsrx.com> Subject: Re: Is there an easy way to determine Lucene versions for segments? Hold on that idea then. An optimize will use three times your index size possibly. > On Oct 6, 2021, at 9:02 AM, Michael Conrad <mich...@newsrx.com> wrote: > > Thanks, > > I think we'll try the full optimize route as we don't have storage to spare > for second copies, etc. > > -Mike > >> On 10/6/21 8:54 AM, Dave wrote: >> Personally I always do a full reindex when going to a new version, just >> safer and you should always be able to do such at any point. However if you >> got the time to spare you can do an optimize and it will force the segments >> all into the current version >> >>>> On Oct 6, 2021, at 8:46 AM, Michael Conrad <mich...@newsrx.com> wrote: >>> >>> Hello all, >>> >>> Is there an easy way to determine Lucene versions for segments? >>> >>> If we were to do a full reindex, rewriting all segments, would that update >>> the segment version to match the current Lucene version in use? >>> >>> We are working on upgrading from Solr 7.7.3 to Solr 8.x but have discovered >>> that several of our collections have segments that are Lucene 6. >>> >>> -Mike >
