I am a bit confused about cluster nodes settings. There is a lot of topics and articles about nodes / shards / replicas settings, but I often find inaccuracies between current (or my) version - articles & topics - documentation.
My version of ES is 5.4. I guess the settings applied to 5.x versions are equal.
Master eligible node
What are proper settings to create node as master-eligible ?
Documentation (https://www.elastic.co/guide/en/elasticsearch/reference/5.4/modules-node.html) says :
A node that has node.master set to true (default), which makes it eligible to be elected as the master node, which controls the cluster.
but further in text the documentation says:
To create a standalone master-eligible node, set:
This topic : https://discuss.elastic.co/t/how-to-create-a-master-eligible-node-in-elasticsearch-5/64669/5
says that node.master setting is all that matters.
There are articles (and documentation) which suggest 3 dedicated master-eligible nodes to be created in cluster as basic configuration.
I want to configure cluster for large number of docs (10 000 000 to 20 000 000), which will be updated and searched. What configuration do you suggest me ?
- 3 node.master nodes + 3 node.data nodes (how many data nodes do I need in this scenario ?)
- 3 node.master, node.data nodes
- 1 node.master node + 2 node.master, node.data nodes
I understand that configuration is individual to requirements and I am not even talking about shards and replicas, but my question is general - what should master eligible node configuration look like for large number of docs to be processed = joined with data nodes, or separated, or ... ?