Reindexing Solr collections after upgrading the cluster
After upgrading to CDP Private Cloud Base, you have to recreate the empty Solr collections with the updated configuration.
Cloudera does not support upgrading the underlying index files from CDH 5 to Cloudera Runtime 7.1.1 or higher, so you must reindex your collections.
Apache Solr does not have dedicated reindexing functionality. To reindex a collection, select the batch indexing procedure most appropriate to your use case.