after adding new parameter and value to the ambari cluster , we need to restart the service to take affect
from ambari GUI restart the service is required , and we can see that because restart button is colored with orange
so my question is
we need API command that restart only the services that restart is required?
in order to restart all relevant services ( that need's restart ) the following syntax is the answer
curl -u admin:admin -H "X-Requested-By: ambari" -X POST -d '{"RequestInfo":{"command":"RESTART","context":"Restart all required services","operation_level":"host_component"},"Requests/resource_filters":[{"hosts_predicate":"HostRoles/stale_configs=true"}]}' http://amb25101.example.com:8080/api/v1/clusters/plain_ambari/requests