Disabled State - Cisco Nexus 9000 Series Configuration Manual

Rapid PVST+
• Receives BPDUs and directs them to the system module.
• Processes BPDUs received from the system module.
• Receives and responds to control plane messages.

Disabled State

A Layer 2 LAN port in the disabled state does not participate in frame forwarding or STP. A Layer 2 LAN
port in the disabled state is virtually nonoperational.
A disabled Layer 2 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
This table lists the possible operational and Rapid PVST+ states for ports and whether the port is included in
the active topology.
Table 9: Port State Active Topology
Operational Status
Enabled
Enabled
Enabled
Disabled
Synchronization of Port Roles
When the device 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 device is synchronized with superior root information received on the root port if all other ports are
synchronized. An individual port on the device 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).
Cisco Nexus 9000 Series NX-OS Layer 2 Switching Configuration Guide, Release 7.x
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Port State
Blocking
Learning
Forwarding
Disabled
Configuring Rapid PVST+ Using Cisco NX-OS
Is Port Included in the Active
Topology?
No
Yes
Yes
No