To confirm your steps:
1) You performed the install.
2) All Hadoop Services were started and running fine, and the Ambari Server and the Ambari Agents were fine
3) You powered off the machines
4) You powered back on the machines and started Ambari Server and the Ambari Agents
5) Now you are unable to get the Hadoop Services to start?
6) Also, confirm what version of Ambari you are using? “ambari-server –version”