I am in process of setting up a cluster. Plan is to make it production setup once the necessary load testing is done.
I will start with :
3 master nodes.
2 coordinating nodes.
5 data nodes.
The number of data nodes will be increased if needed.
From what I know I can use machines with less RAM and Disk space (read 4 GB RAM and 50GB Disk space) for Master nodes and Coordinators.
The data nodes need to have heavier spec'ed (8 GB RAM and 1 TB Disk).
Also is the number of coordinators right? Or should I add more?
I am not an expert in this. I will like the experts to chip in if there are potential issues.
A couple of years ago when I worked with folks to buy hardware 64GB or 96GB tended to be closer to the sweet spot on ram. Elasticsearch will enjoy all the ram you throw at it, mostly in the form of the disk cache.
I've rarely seen coordinating nodes as needed. With a setup like this I wouldn't buy them unless you think you need them from a network architecture standpoint. I've always hit the data nodes directly.
You are just about right on the master eligible nodes specs though.