# Do client nodes help determine the master status

**URL:** <https://discuss.elastic.co/t/do-client-nodes-help-determine-the-master-status/35913>\
**Category:** Elasticsearch\
**Created:** [November 30, 2015, 2:55pm UTC](https://discuss.elastic.co/t/do-client-nodes-help-determine-the-master-status/35913 "2015-11-30T14:55:09Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![yehosef](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/yehosef/32/42175_2.png) [@yehosef](https://discuss.elastic.co/u/yehosef)\
**Post date:** [November 30, 2015, 2:55pm UTC](https://discuss.elastic.co/t/do-client-nodes-help-determine-the-master-status/35913/1 "2015-11-30T14:55:10Z")

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If I had a cluster with 2 data/master nodes and a 3rd client node, will the client node help avoid a split-brain if one of the other nodes in unavailable? I know this config is not recommended - I'm just trying to understand if they help determine master state.

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**Author:** ![Christian\_Dahlqvist](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/christian_dahlqvist/32/4617_2.png) [@Christian\_Dahlqvist](https://discuss.elastic.co/u/Christian_Dahlqvist)\
**Post date:** [November 30, 2015, 3:01pm UTC](https://discuss.elastic.co/t/do-client-nodes-help-determine-the-master-status/35913/2 "2015-11-30T15:01:32Z")

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By definition a client node is not master eligible, so it will not help avoid split-brain scenarios.

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**Author:** ![yehosef](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/yehosef/32/42175_2.png) [@yehosef](https://discuss.elastic.co/u/yehosef)\
**Post date:** [November 30, 2015, 3:18pm UTC](https://discuss.elastic.co/t/do-client-nodes-help-determine-the-master-status/35913/3 "2015-11-30T15:18:26Z")

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ok -thanks.

I'm trying to find the minimal set up for another node to avoid split-brain where there are really only two servers doing the heavy lifting. So if I make the 3rd node a master node, but not data, that would solve the problem?

If there a way to make the cluster prefer one of the data nodes as the master (eg, this 3rd server is really for other things and I don't want any extra work on it.)

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**Author:** ![warkolm](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/warkolm/32/39224_2.png) [@warkolm](https://discuss.elastic.co/u/warkolm)\
**Post date:** [November 30, 2015, 9:32pm UTC](https://discuss.elastic.co/t/do-client-nodes-help-determine-the-master-status/35913/4 "2015-11-30T21:32:43Z")

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If all 3 are master eligible, yes it will help maintain majority quorum.  
You cannot set preference on which will be master though.

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**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [July 5, 2017, 11:34pm UTC](https://discuss.elastic.co/t/do-client-nodes-help-determine-the-master-status/35913/5 "2017-07-05T23:34:42Z")

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