the following API will restart all services that restart action is required ( after paramter changes )
but how to know if any service in ambari cluster need to restart by API ( I mean just to check if restart is needed without to perform restart ? )
# curl -iv -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://$AMBARI_SERVER:8080/api/v1/clusters/$CLUSTER_NAME/reques
Michael-Bronson