# ES High Availability Requirements **URL:** \ **Category:** Elasticsearch\ **Created:** [June 23, 2018, 1:57pm UTC](https://discuss.elastic.co/t/es-high-availability-requirements/137118 "2018-06-23T13:57:59Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![ninewb](https://avatars.discourse-cdn.com/v4/letter/n/f17d59/32.png) [@ninewb](https://discuss.elastic.co/u/ninewb)\ **Post date:** [June 23, 2018, 1:57pm UTC](https://discuss.elastic.co/t/es-high-availability-requirements/137118/1 "2018-06-23T13:57:59Z")
Apologize for my novice questions. I did an initial search and could not find this mentioned anywhere. I wanted to find some documentation or information to solidify my understanding in the required number of nodes for high availability. To assume this at a minimum: 3 master nodes (ive seen recommended, but thought 3 for HA was required) 2 data nodes To dedicate masters, is the above true for the master nodes? Is 3 required? I'd need 2 data nodes in case one fails. Certainly understand that you can dedicate or have multiple roles for each all depending on your use cases and data ingest footprint. Assume in this situation the masters are dedicated and the data nodes are ingest, data, client. ---
**Author:** ![DavidTurner](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/davidturner/32/22453_2.png) [@DavidTurner](https://discuss.elastic.co/u/DavidTurner)\ **Post date:** [June 24, 2018, 8:42pm UTC](https://discuss.elastic.co/t/es-high-availability-requirements/137118/2 "2018-06-24T20:42:40Z")
> [@ninewb](#): > > To dedicate masters, is the above true for the master nodes? Is 3 required? Yes. [Node | Elasticsearch Guide [8.11] | Elastic](https://www.elastic.co/guide/en/elasticsearch/reference/current/modules-node.html#split-brain) says: > To be able to remain available when one of the master-eligible nodes fails, clusters should have at least three master-eligible nodes, with minimum\_master\_nodes set accordingly. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 22, 2018, 8:42pm UTC](https://discuss.elastic.co/t/es-high-availability-requirements/137118/3 "2018-07-22T20:42:43Z")
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