Please understand my question, we don't want to store & set such settings in elasticsearch.yml file, as it cumbersome and another management/restart overhead.
So, that's why, taking the route of setting them up via Update API setting, as mentioned in this thread
If you do not fancy restarts and do not want to store these settings in the yaml file, you can also use the cluster update settings API 6 to add a new email account. This also has the advantage, that it gets distributed to all nodes without you having to do anything.
So want to understand is update API not the right way of setting it up and only way it via setting it up in 'elasticsearch.yml' the only way to set mail alerts in Kibana ?
Thanks