I would like to make a script which can maintain multiple servers via SSH. I want to control the authentication/authorization in such a manner that authentication is done by gateway and any other access is routed through this ssh server to internal services without any further authentication/authorization requirements.

So if a user A can log into server_1 for example. He can then ssh to server_2 without any other authentication and do what ever he is allowed to do on server_2 (like shut down mysql, upgrade it and restart it. This could be done via some remote shell script).

The problem that I am trying to solve is to come up with a deployment script for a JavaEE system which involves databases and tomcat instances. They need to be shutdown and re-spawned. The requirement is to have a deployment script which has minimal human interaction as possible for both developers and operation.