Method and apparatus to control routing convergence during node reboot by entering a freeze state that inhibits routing convergence during the reboot process

摘要

In one embodiment, a technique may enable control of routing convergence in a computer network during reboot of a node of a routing topology represented by a directed acyclic graph (DAG). The rebooting node, e.g., a DAG root node, may transmit a reboot notification message to nodes of the routing topology indicating that the rebooting node is unavailable during a subsequent reboot process. In response to receiving and processing the reboot notification message, the nodes of the routing topology may enter a DAG freeze state that inhibits (prevents) routing convergence in the routing topology during the reboot process so as prevent adverse consequences on network stability, such as collapse of the DAG. Thereafter upon completion of the reboot process, the rebooting node may transmit a clear message to the nodes of the routing topology that instructs the nodes to exit the DAG freeze state.