On 7/7/2015 4:08 AM, anil.chandgude wrote: > currently I am using apache-solr1.4 which does not contain lucene > internally .So w used lucene 2.9 jar for that to get work. > > Now we want to migrate from solr version 1.4 to 4.7 due to jdk version > issue(we have jdk1.6 only ) > > But before migrating to 4.7 , I am trying solr3.1.0 version. But it > seems that there is no any big changes between two. > > so please guide me for version upgradation. Which steps should I take > for that.
Solr 1.4 should have Lucene in it. I used Solr 1.4.0 and 1.4.1 without downloading any Lucene binaries, they were included in the .war file. This version does use Lucene 2.9. The only place I know of where Solr and Lucene are separated is in Debian/Ubuntu packages. Starting in 3.1.0, the Lucene version and Solr version in each release are the same number. Solr 3.x is largely similar to 1.4.x. Version 4.0 is where things became very different. The jump from 4.x to 5.0 is also quite large. I strongly recommend that you rebuild your index entirely when you upgrade. If you can't do that for some reason, be aware that each version of Lucene can only read indexes as far back as the previous major version, so Solr 4.7 cannot read an index built by the Lucene 2.9 that's used in Solr 1.4. If you upgrade to a 3.x version first, you'll need to optimize each index so that it is completely re-written in the new format. When upgrading, you should look closely at the CHANGES.txt and read the section for each version between the version you start with and the version you are going to. You should also look at the example solrconfig and schema included with the old version and the new version, and compare them to see what's changed, so you will know what you might want to change in your own config/schema. Even better would be to start with the example config and change it to meet your requirements. It would be a good idea to upgrade your Java version and run a newer Solr version than 4.7. Only Java 7 is required, but there are some very good performance and memory handling improvements in Java 8. Both Java 6 and Java 7 have reached End of Support from Oracle, so there won't be any new versions unless a major security problem is found. Only Java 8 will continue to see new versions. Thanks, Shawn
