Configuring Pvst Simulation Globally; Configuring Pvst Simulation Per Port - Cisco Nexus 3000 series Configuration Manual

Configuring PVST Simulation Globally

Configuring PVST Simulation Globally
You can block this automatic feature either globally or per port. You can enter the global command, and
change the PVST simulation setting for the entire switch while you are in interface command mode.
SUMMARY STEPS
1. switch# configure terminal
2. switch(config)# no spanning-tree mst simulate pvst global
DETAILED STEPS
Command or Action
Step 1 switch# configure terminal
Step 2 switch(config)# no spanning-tree mst
simulate pvst global
This example shows how to prevent the switch from automatically interoperating with a connecting switch
that is running Rapid PVST+:
switch# configure terminal
switch(config)# no spanning-tree mst simulate pvst global

Configuring PVST Simulation Per Port

MST interoperates seamlessly with Rapid PVST+. However, to prevent an accidental connection to a switch
that does not run MST as the default STP mode, you may want to disable this automatic feature. If you disable
PVST simulation, the MST-enabled port moves to the blocking state once it detects it is connected to a Rapid
PVST+-enabled port. This port remains in the inconsistent state until the port stops receiving BPDUs, and
then the port resumes the normal STP transition process.
You can block this automatic feature either globally or per port.
SUMMARY STEPS
1. switch# configure terminal
2. switch(config)# interface {{type slot/port} | {port-channel number}}
3. switch(config-if)# spanning-tree mst simulate pvst disable
4. switch(config-if)# spanning-tree mst simulate pvst
5. switch(config-if)# no spanning-tree mst simulate pvst
Cisco Nexus 3000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.0(3)U1(1)
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Purpose
Enters configuration mode.
Disables all interfaces on the switch from automatically interoperating
with connected switch that is running in Rapid PVST+ mode. The default
for this is enabled; that is, by default, all interfaces on the switch operate
seamlessly between Rapid PVST+ and MST.
Configuring Multiple Spanning Tree