Synchronizing routing information of control plane and forwarding plane gracefully

High availability in networks has become increasingly critical. Although the graceful restart mechanism makes the restarting router continue forwarding packets, the routing information between the control plane and the forwarding plane tends be inconsistent after the router completes its restart. The routing information inconsistency has a great influence on the forwarding behavior. Some actions must be taken to synchronize them. We think the synchronizing process should be graceful to minimize the negative effect of the router restart and keep it non-stop forwarding. So we present an algorithm PFGSA (prefixes file based graceful synchronizing algorithm) in the case that the control plane cannot get the forwarding plane routing information. The analysis and test results of the algorithm show that the control plane can synchronize the routing information in relatively short time. We believe the availability in networks will be increased further with the implementation of our algorithm