Applying Stp Extension Features; Pvst Simulation - Cisco Nexus 7000 Series Configuration Manual

Configuring STP Extensions Using Cisco NX-OS
put into a root-inconsistent (blocked) state. After the port stops receiving superior BPDUs, the port is unblocked
again. Through STP, the port moves to the forwarding state. Recovery is automatic.
When you enable Root Guard on an interface, this functionality applies to all VLANs to which that interface
belongs.
You can use Root Guard to enforce the root bridge placement in the network. Root Guard ensures that the
port on which Root Guard is enabled is the designated port. Normally, root bridge ports are all designated
ports, unless two or more of the ports of the root bridge are connected. If the bridge receives superior BPDUs
on a Root Guard-enabled port, the bridge moves this port to a root-inconsistent STP state. In this way, Root
Guard enforces the position of the root bridge.
You cannot configure Root Guard globally.

Applying STP Extension Features

We recommend that you configure the various STP extension features through your network as shown in this
figure. Bridge Assurance is enabled on the entire network. You should enable either BPDU Guard or BPDU
Filtering on the host interface.
Figure 21: Network with STP Extensions Correctly Deployed

PVST Simulation

MST interoperates with Rapid PVST+ with no need for user configuration. The PVST simulation feature
enables this interoperability.
Note PVST simulation is enabled by default when you enable MST. By default, all interfaces on the device
interoperate between MST and Rapid PVST+.
Cisco Nexus 7000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.x
Applying STP Extension Features
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