What do the server log files tell you? catalina.out, exceptions.log, node.log of each Informatica node, to name the most important ones?
As the administrator tool doesn't start AND the client tools can't connect, it's pretty likely that the service manager doesn't start at all. Did you check using "ps" whether the two basic Java processes exist?
I checked the logs but didn't find any errors. The 2 java processes we also running (checked with ps).
I solved the problem by reinstalling the whole version from scratch.