I've recently started using elasticsearch and I'm having trouble
understanding when I need to reindex data.
- What operations cause me to need to reindex data?
- Which of these require creating a new index and for which can I simply
reuse the same index?
- Are there settings that require the ES nodes to be restarted after
- How do I reindex online if I need to create a new index? I can use a
scan search to copy the documents from one index to another and then switch
the alias to point to the new index, but it would seem that I'd have to
take my regular indexing process offline or have it writing to both or else
the two indexes would not have the same documents when I switch the alias.