# Dedicated master node and client node **URL:** \ **Category:** Elasticsearch\ **Created:** [December 23, 2014, 3:28pm UTC](https://discuss.elastic.co/t/dedicated-master-node-and-client-node/21371 "2014-12-23T15:28:46Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Han\_JU](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/han_ju/32/962_2.png) [@Han\_JU](https://discuss.elastic.co/u/Han_JU)\ **Post date:** [December 23, 2014, 3:28pm UTC](https://discuss.elastic.co/t/dedicated-master-node-and-client-node/21371/1 "2014-12-23T15:28:46Z")
Hi, Currently in our ElasticSearch cluster we have one dedicated master node (master: true, data: false) and it's also the nodes that receives all requests. This is bad and we want to change it. Here's some questions: 1. Is it a good idea to merge dedicated master nodes with client nodes? Say in the cluster, we have 3 machines at dedicated master nodes and we do some kind of round robin DNS on these 3 for incoming requests. 2. If we opt for separated, dedicated master, could we use smaller instances? Say 3 machines of m3.medium. 3. In general, what's the general suggestion for a cluster setup? We are currently talking about: 5 data nodes, 3 dedicated master node and 2 client nodes. Thanks! -- 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). To view this discussion on the web visit [https://groups.google.com/d/msgid/elasticsearch/4a6ad3d7-b8dd-4e7d-8395-a583b3b70df4%40googlegroups.com](https://groups.google.com/d/msgid/elasticsearch/4a6ad3d7-b8dd-4e7d-8395-a583b3b70df4%40googlegroups.com). For more options, visit [https://groups.google.com/d/optout](https://groups.google.com/d/optout). ---
**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:** [December 23, 2014, 10:21pm UTC](https://discuss.elastic.co/t/dedicated-master-node-and-client-node/21371/2 "2014-12-23T22:21:44Z")
1. That is ok, but just make sure you size the heap to account for large queries (ie aggs) or your master could still OOM (which is bad). You may find as your cluster grows it'll make sense to split the masters and clients. 2. Should be ok, the master doesn't need much heap. But you don't want to go smaller than that. 3. Depends. Unless those nodes are massive and you are doing a _lot_ of heavy queries then I (personally) wouldn't bother with masters or clients, and just round robin with your existing nodes. If you are combining master+data+client nodes, then make sure you monitor them for heap use 🙂 On 24 December 2014 at 02:28, Han JU [ju.han.felix@gmail.com](mailto:ju.han.felix@gmail.com) wrote: > Hi, > > Currently in our Elasticsearch cluster we have one dedicated master node > (master: true, data: false) and it's also the nodes that receives all > requests. This is bad and we want to change it. > Here's some questions: > > 1. Is it a good idea to merge dedicated master nodes with client nodes? > Say in the cluster, we have 3 machines at dedicated master nodes and we do > some kind of round robin DNS on these 3 for incoming requests. > 2. If we opt for separated, dedicated master, could we use smaller > instances? Say 3 machines of m3.medium. > 3. In general, what's the general suggestion for a cluster setup? We are > currently talking about: 5 data nodes, 3 dedicated master node and 2 client > nodes. > > Thanks! > > -- > 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). > To view this discussion on the web visit > [https://groups.google.com/d/msgid/elasticsearch/4a6ad3d7-b8dd-4e7d-8395-a583b3b70df4%40googlegroups.com](https://groups.google.com/d/msgid/elasticsearch/4a6ad3d7-b8dd-4e7d-8395-a583b3b70df4%40googlegroups.com) > [https://groups.google.com/d/msgid/elasticsearch/4a6ad3d7-b8dd-4e7d-8395-a583b3b70df4%40googlegroups.com?utm\_medium=email&utm\_source=footer](https://groups.google.com/d/msgid/elasticsearch/4a6ad3d7-b8dd-4e7d-8395-a583b3b70df4%40googlegroups.com?utm_medium=email&utm_source=footer) > . > For more options, visit [https://groups.google.com/d/optout](https://groups.google.com/d/optout). -- 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). To view this discussion on the web visit [https://groups.google.com/d/msgid/elasticsearch/CAEYi1X\_8%3DX79-NeqDfoOc-OH5\_8YG6eK\_6O-XvZT2QbLdak1uA%40mail.gmail.com](https://groups.google.com/d/msgid/elasticsearch/CAEYi1X_8%3DX79-NeqDfoOc-OH5_8YG6eK_6O-XvZT2QbLdak1uA%40mail.gmail.com). For more options, visit [https://groups.google.com/d/optout](https://groups.google.com/d/optout). ---
**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, 12:42am UTC](https://discuss.elastic.co/t/dedicated-master-node-and-client-node/21371/3 "2017-07-06T00:42:06Z")