This paper discusses an approach that supporting GR mechanism in OSPFv3 protocol to avoid the routing oscillation and data forwarding interruption during router restarting, thereby improving the reliability of the network. Based on the realization of OSPFv3 basic functions, it focuses on the working principle and the concrete realization of IETF standard GR mechanism, analysis the running process and message interaction of OSPFv3 GR in detail. The test results show that the GR mechanism can ensure the data forwarding flow without interruption during protocol restarting.