Fault Management functionality traditionally includes fault detection, generation of alarms, clearing of alarms, alarm forwarding and filtering, storage and retrieval of alarms, correlation of alarms and events, alarm root cause analysis and fault recovery. With introduction of virtualized network functions (VNFs) into mobile networks, Fault Management functionality is distributed over different functional blocks. These different functional blocks may be located at different levels such as NFV Infrastructure (NFVI) level, NE level, NFV Management and Orchestration level and 3GPP network management level.
The decoupling of software from hardware by means of virtualization changes the way in which the faults were managed in non-virtualized NE deployments:
Physical hardware faults of NFVI are detected by NFVI and corrected jointly with the support from NFV-MANO. Only information about those faults (e.g. faults corresponding to the virtualized resources) that affect the proper functioning of VNF needs to be provided to 3GPP management system.
VNF-related virtualized resource fault information needs to be sent from NFV-MANO to 3GPP management system, and then 3GPP management system can take some necessary actions.
VNF application fault information needs to be sent from the VNF instance to the corresponding 3GPP management system that is responsible for taking some necessary actions.
VNF virtualization-specific fault information is detected by VNF and needs to be sent from the VNF instance to both the VNFM and the corresponding 3GPP management system so that they can take necessary actions accordingly.