Is there a server lifetime setting anywhere?

Hi, I have started a fusion server a few days ago, the application in server mode was still running today but no client were able to reach it. Not only that, I was even able to run another application in server mode, which was then recognized by the clients. Does anyone know why that is? Is there a limited time in which an application in server mode is recognized as the server? The logs from the original server did not report any error.