# Minimum\_master\_node not working as expected **URL:** \ **Category:** Elasticsearch\ **Created:** [June 24, 2013, 6:12pm UTC](https://discuss.elastic.co/t/minimum-master-node-not-working-as-expected/12527 "2013-06-24T18:12:36Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Scott\_Floyd](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/scott_floyd/32/2274_2.png) [@Scott\_Floyd](https://discuss.elastic.co/u/Scott_Floyd)\ **Post date:** [June 24, 2013, 6:12pm UTC](https://discuss.elastic.co/t/minimum-master-node-not-working-as-expected/12527/1 "2013-06-24T18:12:36Z")
Elastic Search Version: 0.90.1 Number of servers: 16 Nodes: 32 (2 nodes per server, each node is named node1-a, node1-b, node2-a, node2-b, etc...) When I use N/2+1 to set the "discovery.zen.minimum\_master\_nodes": discovery.zen.minimum\_master\_nodes: 17 The node will never join the cluster. I can set it to: discovery.zen.minimum\_master\_nodes: 5 And it joins, but setting it to any number above 5 and it all not join. Currently I have 4 hosts in the "discovery.zen.ping.unicast.hosts: " discovery.zen.ping.unicast.hosts: ["node1", "node6", "node11", "node16"] If I change "discovery.zen.minimum\_master\_nodes: 5" to "6" the node will not join the cluster. However if I add an additional host to "discovery.zen.ping.unicast.hosts:" the node will then join the cluster. This behavior is consistant, +1 to master\_node and I need to add a host to unicast setting. What is the relationship between "discovery.zen.minimum\_master\_nodes:" and "discovery.zen.ping.unicast.hosts:"? Also, I know this is related to running two nodes on the same host, but would like to get this working. (Trace Attached) -- 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:** ![Andy\_Wick](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/andy_wick/32/44017_2.png) [@Andy\_Wick](https://discuss.elastic.co/u/Andy_Wick)\ **Post date:** [June 25, 2013, 1:24pm UTC](https://discuss.elastic.co/t/minimum-master-node-not-working-as-expected/12527/2 "2013-06-25T13:24:23Z")
Hopefully someone will answer you in the elasticsearch group. I've actually left this value as 4 in our clusters, so I've never tried the n/2+1 solution. My assumption (no reason or proof 🙂 is that this number has to be less then or equal to the unicast.hosts list. If you added a 5th value would minimum\_master\_nodes of 6 work, and if you added 6th value would 7 work, etc etc. I do set the gateway.recover\_after\_nodes and gateway.expected\_nodes to the number of nodes though. Andy -- 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:** ![Jerome\_Gagnon](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jerome_gagnon/32/2178_2.png) [@Jerome\_Gagnon](https://discuss.elastic.co/u/Jerome_Gagnon)\ **Post date:** [June 25, 2013, 8:13pm UTC](https://discuss.elastic.co/t/minimum-master-node-not-working-as-expected/12527/3 "2013-06-25T20:13:57Z")
+1 I've learned with experience (and pain) that the number of unicast.hosts list must be greater or equals to the n/2+1 set for minimum\_master\_nodes. I don't really know the underlying reason for that though. On Tuesday, June 25, 2013 9:24:23 AM UTC-4, Andy Wick wrote: > Hopefully someone will answer you in the elasticsearch group. I've > actually left this value as 4 in our clusters, so I've never tried the > n/2+1 solution. My assumption (no reason or proof 🙂 is that this number > has to be less then or equal to the unicast.hosts list. If you added a 5th > value would minimum\_master\_nodes of 6 work, and if you added 6th value > would 7 work, etc etc. > > I do set the gateway.recover\_after\_nodes and gateway.expected\_nodes to the > number of nodes though. > > Andy -- 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:** ![Clinton\_Gormley](https://avatars.discourse-cdn.com/v4/letter/c/50afbb/32.png) [@Clinton\_Gormley](https://discuss.elastic.co/u/Clinton_Gormley)\ **Post date:** [June 27, 2013, 1:25pm UTC](https://discuss.elastic.co/t/minimum-master-node-not-working-as-expected/12527/4 "2013-06-27T13:25:32Z")
If this is true, it is a bug. This should not be the intended behaviour. Please can you open an issue describing the exact steps to reproduce this, and we'll take a look at it thanks Clint On 25 June 2013 21:13, Jérôme Gagnon [jerome.gagnon.1@gmail.com](mailto:jerome.gagnon.1@gmail.com) wrote: > +1 I've learned with experience (and pain) that the number of > unicast.hosts list must be greater or equals to the n/2+1 set > for minimum\_master\_nodes. I don't really know the underlying reason for > that though. > > On Tuesday, June 25, 2013 9:24:23 AM UTC-4, Andy Wick wrote: > > > Hopefully someone will answer you in the elasticsearch group. I've > > actually left this value as 4 in our clusters, so I've never tried the > > n/2+1 solution. My assumption (no reason or proof 🙂 is that this number > > has to be less then or equal to the unicast.hosts list. If you added a 5th > > value would minimum\_master\_nodes of 6 work, and if you added 6th value > > would 7 work, etc etc. > > > > I do set the gateway.recover\_after\_\*\*nodes and gateway.expected\_nodes to > > the number of nodes though. > > > > Andy > > -- > 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:** ![drewr](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/drewr/32/7803_2.png) [@drewr](https://discuss.elastic.co/u/drewr)\ **Post date:** [July 3, 2013, 5:56pm UTC](https://discuss.elastic.co/t/minimum-master-node-not-working-as-expected/12527/5 "2013-07-03T17:56:06Z")
Clinton Gormley wrote: > If this is true, it is a bug. This should not be the intended > behaviour. > > Please can you open an issue describing the exact steps to > reproduce this, > and we'll take a look at it Apologies, Scott, for not noting here that I opened an issue for this. Alex closed yours as a duplicate. [unicast.hosts has to seed enough nodes to satisfy minimum\_master\_nodes · Issue #3262 · elastic/elasticsearch · GitHub](https://github.com/elasticsearch/elasticsearch/issues/3262) We're still looking into what exactly happens in this scenario. Drew -- 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, 2:28am UTC](https://discuss.elastic.co/t/minimum-master-node-not-working-as-expected/12527/6 "2017-07-06T02:28:20Z")