MARS: Easing maintenance and interventions for CERN controls

Industrial control systems for the CERN technical infrastructure and accelerator complex consist of a myriad of devices and components geographically distributed around the CERN facilities. In the event of an intervention in such systems, the on-call engineer or the system expert needs detailed information about the nature of the problem, e.g. what device, what problem, intervention procedures, and contextual data like the location of the device, current access conditions to this place, the list of access rights required and whether he/she is granted with these rights. This is of special relevance when the person responsible for the intervention has only limited knowledge of the control system as it is the case for some on-call services. At CERN, this information is scattered over a number of data sources. This paper presents MARS (Maintenance and Assets for contRolS), a web-based tool designed to federate data from heterogeneous sources with the aim of providing support for interventions and maintenance activities. The information can be displayed in a single web page or be accessed through a REST API.