D-Link DGS-6600-48TS Configuration Guide - Page 273

Volume 4-Layer 3 Configurations / Chapter 28-Open Shortest Path First Version 3 (OSPFv3) Chapter Overview Interface state machine The finite state machine implemented in ospf6d is a simple table driven state machine. Any state transition may result in a specific action to be run. The resulting next state can either be a result of the action or is fixed and pre-determined. (See Diagram below) Down UnloopInd Loopback Waiting InterfaceUp Point‐to‐point WaitTimer BackupSeen Backup NeighborChange Election NeighborChange DROther NeighborChange DR Figure 28-1 DOWN In this state, the lower-level protocols have indicated that the interface is unusable. No protocol traffic at all will be sent or received on such an interface. LOOPBACK In this state, the router's interface to the network is looped back. Loopback interfaces are advertised in router-LSAs as single host routes, whose destination is the interface IP address. POINT-TO-POINT Point-to-point networks or virtual links enter this state as soon as the interface is operational. WAITING Broadcast or NBMA interfaces enter this state when the interface gets operational. While in this state no DR/BDR election is allowed. Receiving and sending of Hello packets is allowed and is used to try to determine the identity of the DR/BDR routers. DROTHER The router is neither DR nor BDR on the connected network. In this state the router will only form adjacencies to both the DR and the BDR. All other neighbors will stay in neighbor state 2-WAY. BACKUP DGS-6600 Configuration Guide 273