Configuring Pvst Simulation Per Port - Cisco Nexus 3000 Series Configuration Manual

Configuring PVST Simulation Per Port

Procedure
Step 1
Step 2
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.
Procedure
Step 1
Step 2
Step 3
Step 4
Step 5
Cisco Nexus 3000 Series NX-OS Layer 2 Switching Configuration Guide, Release 6.x
100
Command or Action
switch# configure terminal
switch(config)# no spanning-tree
mst simulate pvst global
Command or Action
switch# configure terminal
switch(config)# interface {{type
slot/port} | {port-channel number}}
switch(config-if)# spanning-tree mst
simulate pvst disable
switch(config-if)# spanning-tree mst
simulate pvst
switch(config-if)# no spanning-tree
mst simulate pvst
Configuring Multiple Spanning Tree
Purpose
Enters global configuration mode.
Disables all interfaces on the switch from automatically
interoperating with connected switch that is running in
Rapid PVST+ mode. By default, all interfaces on the switch
operate seamlessly between Rapid PVST+ and MST.
Purpose
Enters global configuration mode.
Specifies an interface to configure, and enters interface
configuration mode.
Disables specified interfaces from automatically
interoperating with a connected switch that is running
in Rapid PVST+ mode.
By default, all interfaces on the switch operate
seamlessly between Rapid PVST+ and MST.
Reenables the seamless operation between MST and
Rapid PVST+ on specified interfaces.
Sets the interface to the switch-wide MST and Rapid
PVST+ interoperation that you configured using the
spanning-tree mst simulate pvst global command.
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