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Upgrading ElasticSearch–Discovery configuration is required in production mode

While preparing for an ElasticSearch upgrade I checked the Upgrade assistant.

One (critical) issue was mentioned: Discovery configuration is required in production mode

Let’s have a look what the documentation has to mention:

Production deployments of Elasticsearch now require at least one of the following settings to be specified in the elasticsearch.yml configuration file:

  • discovery.seed_hosts
  • discovery.seed_providers
  • cluster.initial_master_nodes
  • discovery.zen.ping.unicast.hosts
  • discovery.zen.hosts_provider

The first three settings in this list are only available in versions 7.0 and above. If you are preparing to upgrade from an earlier version, you must set discovery.zen.ping.unicast.hosts or discovery.zen.hosts_provider.

In our case we don’t want to form a multiple-node cluster. So we ignore the documentation above and instead change the discovery.type to single-node.

For more information about when you might use this setting, see Single-node discovery.

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