Can Solr provide search service when reindexing?

Question

As described in the tile, can Solr provide search service when reindexing? If not, is there a solution cover such scenario?

Answer 1

Until you commit (or auto-commit), no changes submitted to Solr are visible to the client. So you can continue providing the search service. After commit, the searcher is reopened and the clients will see new content.

If the changes are significant, you may consider building them in a separate collection from scratch (on the same or on different server) and then - after it is done - swapping the cores for standalone or changing the alias for the SolrCloud configuration. Either approach will keep the same name but point to your new collection.