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ElasticSearch - Exposing your ElasticSearch instance

ElasticSearch is safe out-of-the-box. If you do a new installation, your ElasticSearch instance is only listening to internal traffic. If you want to make the ElasticSearch API’s accessible outside the VM where you installed it, you have to take some extra steps:

  • Go to the ElasticSearch folder that you configured to store your index and configuration data.
  • Open the ElasticSearch.yml file inside the config folder.
  • Set the network.host value to a non-loopback address. I’ll use 0.0.0.0 but a specific IP address is of course better:

network.host: 0.0.0.0

If you know restart your ElasticSearch instance, you’ll notice that we are not there yet. The node fails to start with the following error message:

[2019-07-10T14:34:59,782][INFO ][o.e.d.DiscoveryModule    ] [ESSRV1] using discovery type [zen] and seed hosts providers [settings]

[2019-07-10T14:35:00,436][INFO ][o.e.n.Node               ] [ESSRV1] initialized

[2019-07-10T14:35:00,436][INFO ][o.e.n.Node               ] [ESSRV1] starting ...

[2019-07-10T14:35:00,634][INFO ][o.e.t.TransportService   ] [ESSRV1] publish_address {10.1.100.236:9300}, bound_addresses {[::]:9300}

[2019-07-10T14:35:00,643][INFO ][o.e.b.BootstrapChecks    ] [ESSRV1] bound or publishing to a non-loopback address, enforcing bootstrap checks

[2019-07-10T14:35:00,647][ERROR][o.e.b.Bootstrap          ] [ESSRV1] node validation exception

[1] bootstrap checks failed

[1]: the default discovery settings are unsuitable for production use; at least one of [discovery.seed_hosts, discovery.seed_providers, cluster.initial_master_nodes] must be configured

[2019-07-10T14:35:00,650][INFO ][o.e.n.Node               ] [ESSRV1] stopping ...

[2019-07-10T14:35:00,666][INFO ][o.e.n.Node               ] [ESSRV1] stopped

[2019-07-10T14:35:00,666][INFO ][o.e.n.Node               ] [ESSRV1] closing ...

[2019-07-10T14:35:00,678][INFO ][o.e.n.Node               ] [ESSRV1] closed

The moment you provided a custom setting for network.host, Elasticsearch assumes that you are moving from development mode to production mode, and upgrades a number of system startup checks from warnings to exceptions. So we have to configure one extra setting; the initial_master_nodes:

cluster.initial_master_nodes: node-1

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