A service appliance can be installed between one or more production servers running service applications and service users. In the event that a production server is unable to provide its service to users, the service appliance can transparently intervene to maintain service availibility. The service appliance is capable of providing the service using a service application that is differently configured or even a different application than the service applications of the production server. The service appliance may include hardware and/or software to monitor, repair, maintain, and update the service application and other associated software applications and components of service appliance. The service appliance may be configured to have a locked state that prevents local running of additional applications other than those provided for prior to entering the locked state, limiting local and remote user administration of and operational control of the operating system and service application.