How many master nodes on a three node cluster on elasticsearch?


(Javier Barroso) #1

Hello,

At https://www.elastic.co/blog/resiliency-elasticsearch I can read:

In Elasticsearch, we actively promote the use of dedicated master nodes
in critical clusters to make sure that there are 3 nodes whose only role
is to be master, a lightweight operational responsibility. By reducing
the amount of resource intensive work that these nodes do (no data
ingestion or search), we greatly reduce the chance of cluster
instability.

But at Role of dedicated master nodes when not elected I can read:

As a followup, any ratio guidelines for indexing nodes vs dedicated
masters. From what I can tell, it wouldn't make much sense to run with
only one-dedicated master node; if that node goes down, your whole cluster
becomes unavailable.

So, how do you configure a 3 node cluster. Are there any priority setting about master election?

May be some like:

at master nodes: master priority 100
at data nodes: master priority 50

Thank you very much !


(Magnus Bäck) #2

If you have a cluster with (in total) three nodes you should make all of them master-eligible. I haven't heard of any master priority/preference setting.


(Javier Barroso) #3

Hello,

Then I should balance to that three nodes. We was thinking having a node for máster operation, and two balanced nodes to receive data and execute the searchs (maybe getting master rol as failover)

Thank you, the setup will be easier, not sure the performance


(system) #4