1. A system comprising: a system to provide services, the system including a plurality of components; a risk analysis device having memory storing instructions and a processor to execution the instructions to: compute, on the basis of risk factor influence information representing a relation between a component of said components having a risk factor and other components of said components which are to be influenced by a state of said component, component characteristic information representing characteristics of each of said risk factors, and service information representing correspondence between said services and said components, a service influence degree corresponding to each of said risk factors with respect to each of said services; compute, on the basis of said service influence degrees, similarities between a specific one of said risk factors and the other ones of said risk factors, and generate and output information including at least a set of pieces of identification information each representing said component corresponding to said risk factor selected on the basis of said similarities; and based on the output information, remove at least two said risk factors simultaneously by one of making one of said components redundant with another component of said components, and replacing said component with another component of said components having higher reliability than said component.