dose ambari cluster needs ssh access between ambari-server machine to all other host

Question

We installed ambari cluster with 3 masters machines

While ambari server installed on master02 linux machine

ambari cluster also include 25 DataNodes machines and 5 kafka's machines

1. dose ambari-server needs ssh access to all other machines in the cluster? ( while ambari cluster is fully installed and working )

Example

 ambari-server # ssh datanode01 

2. dose all files under /root/.ssh/.. on ambari-server machine are used by ambari cluster?