title: How to merge shards in ElasticSearch
body: <p>I launched a ElasticSearch instance several months ago but I overestimated a sizing of an average shard. My shards are fairly small now 400mb max. and I found out that a recommended size should be approx. 50gb (based on a stackoverflow search). I also ran out of maximum shard count and I had to reconfigure it. But the proper approach is to change a logic of shards and basically make shards larger. It is completely doable in my case but the question is how to deal with already existing shards. I can certainly replay data but it will take a LOT of time. So is there a better way how to merge smaller shards into big ones?</p>