Kibana is always migrating from .kibana to .kibana_1 on fresh startup

[lmqnam (Nam Le)]

I'm using Kibana 6.5.4

When staring fresh Kinaba, it always migrates index.

Why does Kibana always migrate index on fresh startup? Please help to explain. Thanks in advance!

I referred similar case https://www.elastic.co/guide/en/kibana/6.5/upgrade-migrations.html
But that case is 'Kibana is upgraded'.

{"type":"log","@timestamp":"2019-09-26T04:45:55Z","tags":["info","Sentinl","init_indices"],"pid":1,"message":"checking watcher_alarms-2019.09.26 index ..."}
{"type":"log","@timestamp":"2019-09-26T04:45:55Z","tags":["info","migrations"],"pid":1,"message":"Creating index .kibana_1."}
{"type":"log","@timestamp":"2019-09-26T04:45:55Z","tags":["info","migrations"],"pid":1,"message":"Pointing alias .kibana to .kibana_1."}
{"type":"log","@timestamp":"2019-09-26T04:45:55Z","tags":["info","migrations"],"pid":1,"message":"Finished in 126ms."}

[jbudz (Jon Budzenski)]

It's mostly part of the legacy conversion process - in this case it's probably too verbose. We transitioned from saving state in .kibana to saving state in a numbered kibana index that gets upgraded between versions. .kibana going forward is an alias pointing to the most recent version.