How to define the number of fragments on ElasticSearch?


I've installed, a elasticsearch cluster with three nodes, i pretend to use for search emails.

On my platform i'll have 40k mails per month. So my question is How to define the shards number and replicas number on ElasticSearch?

Are there best practices for the measure?

Thanks in advance.

You can define it in the elasticsearch.yml file or when you create a template for an index.