On this page, there is an example of Splunk cluster with - 1 SH - 2 indexers
But in the "cluster administration course, it is explicitly said: - the master nod must be run a dedicated node - the master cannot be shared with the search head node So the minimum cluster should be : - 1 SH - 2 indexers - 1 Master
Can someone explain this to me? - Why there is no master node on the recommendation page? -If it's possible to share the search head and cluster master in production
The topic in the Capacity Planning Manual just covers the relative requirements for search heads and indexers, based on your capacity needs.
If you set up an indexer cluster, there are a large number of other issues that you need to accommodate, including the cluster node requirements. Those are not specifically related to capacity concerns, and thus are not covered in the Capacity Planning Manual.
Cluster Master and Master Node are the same thing!
When you speak of "recommendation page" are you speaking of Hardware reference o what else?
If you're speaking of Hardware reference, there isn't any reference for CM, but if you run an Health Check from the Monitoring Console, youll' have a warning for the configuration, that should be at least 12 CPUs and 12 GB of RAM.
Cluster Master MUST have a dedicated server, can eventually be shared with low impact instances as Deployer or License Master, but NEVER with Deployment Server, Indexer or Search Head.