问题
I am looking for migrating the data from elastic search version 5.5 to 7.7, I found the following two ways,
1) Re_Index API using Java API : https://www.elastic.co/guide/en/elasticsearch/client/java-rest/master/java-rest-high-document-reindex.html#java-rest-high-document-reindex
which looks easy (as it involves java code) and able to see all the possible cases for moving all the documents from version 5.5 to 7.7
2) Re_Index API using Curl : https://www.elastic.co/guide/en/elasticsearch/reference/current/reindex-upgrade-remote.html
3) Using logstash : https://discuss.elastic.co/t/elasticsearch-reindex-using-logstash/79143
Which is the most proper way to do this? Any advantages or disadvantages in the above?
来源：https://stackoverflow.com/questions/62431157/reindex-api-vs-using-logstash-for-reindexing-from-elastic-search-5-5-remote-to