How to check if a master node auto-election is enabled?

We have installed ES 6.2.4 and have 3 master node setup.

  1. Is there a way to check if auto-election of master node is enabled in case active master goes down?
  2. do elastic search always do auto-election (or) disabling auto-election is also allowed in some es versions?

Note: we have set "discovery.zen.minimum_master_nodes: 2" such that split brain won't occur.

Yes, elections are automatic and no, that cannot be disabled. I can't imagine why you might want to prevent the election of a new master when the old one fails.

You are using a very old version, long past EOL, and should upgrade as a matter of urgency.

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@DavidTurner, Thanks for the quick response. I'm actually going through ES documentation and comparing the same with the readymade prod cluster we have. Nowhere I was able to find out if auto election is strictly automatic in the docs (May be I didn't read it properly). So, I was looking for a config that enables/disables auto-master election in the nodes elasticsearch.toml files to see if it's set to true.

Thanks again!. We will soon migrate to newer version.

As a follow up question, if the active Master goes down, from the remaining 2 master-eligible nodes, either of them can become active master. But which nodes are involved in the selection process? Only datanodes?

Maybe see these docs?

Discovery is the process by which the cluster formation module finds other nodes with which to form a cluster. This process runs when you start an Elasticsearch node or when a node believes the master node failed and continues until the master node is found or a new master node is elected.

Disabling this makes no sense.

Only the master-eligible nodes.

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@DavidTurner Yes, only the master-eligible nodes can become next Master.
I'll rephrase,
Which nodes elect/vote the master-eligible nodes?

In this doc: Zen Discovery | Elasticsearch Reference [6.2] | Elastic

Under "Master Election" section, it says, "When the master node stops or has encountered a problem, the cluster nodes start pinging again and will elect a new master."

Do "cluster nodes" here mean only "datanodes" or "masternodes" or both.

As I said, only the master-eligible nodes are involved in the selection process, although all the nodes perform pinging.

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