Set minimum_master_nodes

[bert_vervaele]

Hey,

I was wondering if I had to set the "discovery.zen.minimum_master_nodes" setting in the yml of all my nodes in the cluster or only the master eligible ones?

Kind regards Bert

[Bernt_Rostad]

I'm pretty sure you only need to set this in the master eligible nodes elasticsearch.yml files because the data nodes doesn't need to know this setting.

But you can also set this dynamically in a cluster, using a curl command like this:

curl -X PUT "http://localhost:9250/_cluster/settings" -H "Content-Type: application/json" -d '{
    "transient" : {
        "discovery.zen.minimum_master_nodes" : 2
    }
}'

This lets you add more master nodes and update the minimum_master_nodes setting without having to restart the old master eligible nodes.