# Minimum number of nodes for availability: 2 or 3? **URL:** \ **Category:** Elasticsearch\ **Created:** [June 18, 2013, 4:48pm UTC](https://discuss.elastic.co/t/minimum-number-of-nodes-for-availability-2-or-3/12463 "2013-06-18T16:48:51Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Edward\_Sargisson\_2](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/edward_sargisson_2/32/2267_2.png) [@Edward\_Sargisson\_2](https://discuss.elastic.co/u/Edward_Sargisson_2)\ **Post date:** [June 18, 2013, 4:48pm UTC](https://discuss.elastic.co/t/minimum-number-of-nodes-for-availability-2-or-3/12463/1 "2013-06-18T16:48:51Z")
Hi all, So what is the minimum number of nodes to have in a cluster to be nicely available? 2 or 3? I think that two may be insufficient because if the nodes go out of communication with each other you run the risk of the split brain problem. The mitigation here is to have 3 nodes (with minimum master nodes set to 2). I suppose an alternative is to have a small routing only node to help with master election and 2 storage nodes. Is my understanding sound or am I missing something? Many thanks, Edward -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [elasticsearch+unsubscribe@googlegroups.com](mailto:elasticsearch+unsubscribe@googlegroups.com). For more options, visit [https://groups.google.com/groups/opt\_out](https://groups.google.com/groups/opt_out). ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [June 18, 2013, 5:06pm UTC](https://discuss.elastic.co/t/minimum-number-of-nodes-for-availability-2-or-3/12463/2 "2013-06-18T17:06:36Z")
I prefer to have 3 nodes (data and master). My 2 cents -- David 😉 Twitter : @dadoonet / @elasticsearchfr / @scrutmydocs Le 18 juin 2013 à 18:48, Edward Sargisson [esarge@pobox.com](mailto:esarge@pobox.com) a écrit : > Hi all, > So what is the minimum number of nodes to have in a cluster to be nicely available? 2 or 3? > > I think that two may be insufficient because if the nodes go out of communication with each other you run the risk of the split brain problem. The mitigation here is to have 3 nodes (with minimum master nodes set to 2). > > I suppose an alternative is to have a small routing only node to help with master election and 2 storage nodes. > > Is my understanding sound or am I missing something? > > Many thanks, > Edward > > -- > You received this message because you are subscribed to the Google Groups "elasticsearch" group. > To unsubscribe from this group and stop receiving emails from it, send an email to [elasticsearch+unsubscribe@googlegroups.com](mailto:elasticsearch+unsubscribe@googlegroups.com). > For more options, visit [https://groups.google.com/groups/opt\_out](https://groups.google.com/groups/opt_out). -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [elasticsearch+unsubscribe@googlegroups.com](mailto:elasticsearch+unsubscribe@googlegroups.com). For more options, visit [https://groups.google.com/groups/opt\_out](https://groups.google.com/groups/opt_out). ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 6, 2017, 2:30am UTC](https://discuss.elastic.co/t/minimum-number-of-nodes-for-availability-2-or-3/12463/3 "2017-07-06T02:30:34Z")