HP Cisco Nexus 5000 Cisco Nexus 5000 Series Switch CLI Software Configuration - Page 147

Chapter 8 Configuring Rapid PVST+ Information About Rapid PVST+ Send feedback to [email protected] • Incorporates the end station location information into its address database. • Receives BPDUs and directs them to the system module. • Processes BPDUs received from the system module. • Receives and responds to network management messages. Disabled State A LAN port in the disabled state does not participate in frame forwarding or STP. A LAN port in the disabled state is virtually nonoperational. A disabled LAN port performs as follows: • Discards frames received from the attached segment. • Discards frames switched from another port for forwarding. • Does not incorporate the end station location into its address database. (There is no learning, so there is no address database update.) • Does not receive BPDUs from neighbors. • Does not receive BPDUs for transmission from the system module. Summary of Port States Table 8-3 lists the possible operational and Rapid PVST+ states for ports and the corresponding inclusion in the active topology. Table 8-3 Port State Active Topology Operational Status Enabled Enabled Enabled Disabled Port State Blocking Learning Forwarding Disabled Is Port Included in the Active Topology? No Yes Yes No Synchronization of Port Roles When the switch receives a proposal message on one of its ports and that port is selected as the new root port, Rapid PVST+ forces all other ports to synchronize with the new root information. The switch is synchronized with superior root information received on the root port if all other ports are synchronized. An individual port on the switch is synchronized if either of the following applies: • That port is in the blocking state. • It is an edge port (a port configured to be at the edge of the network). If a designated port is in the forwarding state and is not configured as an edge port, it transitions to the blocking state when the Rapid PVST+ forces it to synchronize with new root information. In general, when the Rapid PVST+ forces a port to synchronize with root information and the port does not satisfy any of the above conditions, its port state is set to blocking. OL-16597-01 Cisco Nexus 5000 Series Switch CLI Software Configuration Guide 8-13