So I tried to reach the ResourceManager through port 8088
curl -H "X-Requested-By: ambari; Content-Type: application/json" -X GET -u admin:password resourse.manager.host:8088/ws/
and I get a response, however the remaining part of the url to interact with resource management fails:
resource.manager.host:8088/ws/v1/mapreduce2 (or yarn/spark etc)
Any thoughts on what I'm doing wrong with the web service request?
You were reading documentation of Hadoop 3.0, which is unreleased yet (alpha 2 is out, but that's not production ready).
The most recent version of Hadoop in production is 2.7 for which you can find the respective guide here: