Hi, I have questions about the IndexUpgrader tool. - I want to upgrade from Solr 4 to Solr 7. Can I run upgrade the index from 4 to 5 then 5 to 6 and finally 6 to 7 using appropriate version of the IndexUpgrader but without loading the Index in the Solr at all during the successive upgrades.
- The note in the tool says "This tool only keeps last commit in an index". Does this mean I have optimize the index before running the tool? - There is another note about partially upgraded index. How can the index be partially upgraded. One scenario I can think of is 'If I upgraded let's say from Solr 5 to Solr 6 and then added some documents. The new documents will be in Lucerne 6 format already, while old documents will still be Solr 5 format’ Is my understanding correct?
