Request help / steps to upgrade from apache solr 7.x to 8.x

Hi, I have some requirements those are I mentioned below, please do the needful 1. I have an apache solr 7.7.3 version. Want to upgrade to the 8.5.2 version. Want to upgrade JDK to version 8 from 6 Please advise the steps for the same. 2. How to take backup of Solr data? 3. How to

Request help / steps to upgrade from apache solr 7.x to 8.x

Export the entire data from version 7.7.3 to a CSV file? 4. How to import that CSV file to the upgraded 8.5.2 version? Thanks and Regards, Utsav Sahavasi Developer @Capgemini 9686410580