Elasticsearch domains should be configured with at least three dedicated master nodes

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Description

Verifies that Elasticsearch domains have at least three dedicated master nodes configured for cluster stability.

To configure an Elasticsearch domain with at least three dedicated master nodes, follow these steps:

Open the Amazon Elasticsearch Service console at https://console.aws.amazon.com/es/.
Choose the domain that you want to modify.
In the navigation pane, under Domain configuration, choose Elasticsearch cluster.
Enable 'Dedicated master' and set the number of dedicated master nodes to 3 or more.
Choose Save changes.

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