Elasticsearch cluster name in yml file

[stephenb (Stephen Brown)]

When renaming a cluster requires full restart... Ie shut down entire cluster then start them... You can do 1 by one but you should be able to start them all and if properly configured the cluster will sort itself out

How to change the cluster name of an elk cluster with 3 master nodes

That's correct, you will have to shut down all the nodes, adjust their config, and then start them all up again. Edit: I don't see this in the docs today so I opened #95858.

Cluster Name Settings