Cisco Nexus 9000 Series Configuration Manual page 167

Configuring STP Extensions Using Cisco NX-OS
Bridge Assurance
moves into the blocking state and is not used in the root port calculation. Once that port receives a BPDU, it
resumes the normal spanning tree transitions.
This figure shows a normal STP topology.
Figure 14: Network with Normal STP Topology
This figure demonstrates a potential network problem when the device fails and you are not running Bridge
Assurance.
Figure 15: Network Problem without Running Bridge Assurance
Cisco Nexus 9000 Series NX-OS Layer 2 Switching Configuration Guide, Release 7.x
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