Enabling and configuring R-PVST+ on a system

The ports and parameters can be configured individually by:

Entering the commands in steps 1 and 2
Running the relevant addition steps and parameter commands
Verifying the result
Saving the configuration

For detailed descriptions of the parameters and features, see the sections STP parameters and STP features.

Enter global configuration mode.
```
device# configure terminal
```
Enable R-PVST+.
```
device(config)# protocol spanning-tree rpvst
```
You can shut down R-PVST+ by entering the shutdown command when in rpvst configuration mode.
Configure the bridge priority for the common instance.
```
device(config-rpvst)# bridge-priority 4096
```
Valid values range from 0 through 61440 in increments of 4096. Assigning a lower priority value indicates that the bridge might become root.

Configure the forward delay parameter.

device(config-rpvst)# forward-delay  20

Configure the hello time parameter.
```
device(config-rpvst)# hello-time 8
```
Configure the maximum age parameter.
```
device(config-rpvst)# max-age 22
```
Specify the transmit hold count.
```
device(config-rpvst)# transmit-holdcount 5
```
This command configures the maximum number of BPDUs transmitted per second. The range of values is 1 through 10.
Configure VLANs.
1. Configure VLAN 100 with a priority of 0.
```
device(config-rpvst)# vlan 100 priority 0
```
  Valid priority values range from 0 through 61440 in multiples of 4096.
2. Configure VLAN 201 with a priority of 12288.
```
device(config-rpvst)# vlan 201 priority 12288
```
3. Configure VLAN 301 with a priority of 20480.
```
device(config-rpvst)# vlan 301 priority 20480
```

Set the switching characteristics for interface 0/3.

Enter interface configuration mode.

device(config-rpvst)# interface ethernet 0/3

Set the switching characteristics of the interface.
```
device(conf-if-eth-0/3)# switchport
```

Set the interface mode to trunk.

device(conf-if-eth-0/3)# switchport mode trunk

Add VLAN 100 as a member VLAN.

device(conf-if-eth-0/3)# switchport trunk allowed vlan add 100

Add VLAN 201 as a member VLAN.

device(conf-if-eth-0/3)# switchport trunk allowed vlan add 201

Add VLAN 301 as a member VLAN.

device(conf-if-eth-0/3)# switchport trunk allowed vlan add 301

Enable spanning tree on the interface.

device(conf-if-eth-0/3)# no spanning-tree shutdown

Return to privileged EXEC mode.
```
device(conf-if-eth-0/3)# exit 
```

Set the switching characteristics for interface 0/4.

Enter interface configuration mode.

device(config-rpvst)# interface ethernet 0/4

Set the switching characteristics of the interface.
```
device(conf-if-eth-0/4)# switchport
```

Set the interface mode to trunk.

device(conf-if-eth-0/4)# switchport mode trunk

Add VLAN 100 as a member VLAN.

device(conf-if-eth-0/4)# switchport trunk allowed vlan add 100

Add VLAN 201 as a member VLAN.

device(conf-if-eth-0/4)# switchport trunk allowed vlan add 201

Add VLAN 301 as a member VLAN.

device(conf-if-eth-0/4)# switchport trunk allowed vlan add 301

Enable spanning tree on the interface.

device(conf-if-eth-0/4)# no spanning-tree shutdown

Return to privileged EXEC mode.
```
device(conf-if-eth-0/4)# exit  
```

To interoperate with switches other than VDX switches in R-PVST+ mode, you must configure the interface that is connected to that switch.
1. Enter interface configuration mode for the port that interoperates with a VDX switch.
```
device(config)# interface ethernet 0/12
```
2. Specify the MAC address for the device.
```
device(conf-if-eth-0/12)# spanning-tree bpdu-mac 0100.0ccc.cccd
```
3. Enable spanning tree on the interface.
```
device(conf-if-eth-0/12)# no spanning-tree shutdown  
```
4. Return to privileged EXEC mode.
```
device(conf-if-eth-0/12)# end  
```

Verify the configuration.

device# show spanning-tree 

VLAN 1

 Spanning-tree Mode: Rapid PVST Protocol

 Root Id: 0001.01e0.5200.0180 (self)
 Bridge Id: 0001.01e0.5200.0180

 Root Bridge Forward Delay: 15; Hello Time: 2; Max Age: 20; Max-hops: 20
 Configured Forward Delay: 20; Hello Time: 8; Max Age: 22; Max-hops: 20
 Tx-HoldCount 5
 Number of topology change(s): 0

 Bpdu-guard errdisable timeout: disabled
 Bpdu-guard errdisable timeout interval: 300 sec

 Port Et 0/3 enabled
    Ifindex: 201351168; Id: 8001; Role: Disabled; State: Disabled
    Designated Path Cost: 0
    Configured Path Cost: 20000000
    Designated Port Id: 0; Port Priority: 128
    Designated Bridge: 0000.0000.0000.0000
    Number of forward-transitions: 0
    Version: Per-VLAN Spanning Tree Protocol - Received None - Sent STP
    Portfast: off
    Configured Root guard: off; Operational Root guard: off
    Bpdu-guard: off
    Link-type: point-to-point
    Received BPDUs: 0; Sent BPDUs: 0

 Port Et 0/4 enabled
    Ifindex: 201359360; Id: 8002; Role: Disabled; State: Disabled
    Designated Path Cost: 0
    Configured Path Cost: 20000000
    Designated Port Id: 0; Port Priority: 128
    Designated Bridge: 0000.0000.0000.0000
    Number of forward-transitions: 0
    Version: Per-VLAN Spanning Tree Protocol - Received None - Sent STP
    Portfast: off
    Configured Root guard: off; Operational Root guard: off
    Bpdu-guard: off
    Link-type: point-to-point
    Received BPDUs: 0; Sent BPDUs: 0

VLAN 100

 Spanning-tree Mode: Rapid PVST Protocol

 Root Id: 0064.01e0.5200.0180 (self)
 Bridge Id: 0064.01e0.5200.0180

 Root Bridge Forward Delay: 15; Hello Time: 2; Max Age: 20; Max-hops: 20
 Configured Forward Delay: 20; Hello Time: 8; Max Age: 22; Max-hops: 20
 Tx-HoldCount 5
 Number of topology change(s): 0

 Bpdu-guard errdisable timeout: disabled
 Bpdu-guard errdisable timeout interval: 300 sec

 Port Et 0/3 enabled
    Ifindex: 201351168; Id: 8001; Role: Disabled; State: Disabled
    Designated Path Cost: 0
    Configured Path Cost: 20000000
    Designated Port Id: 0; Port Priority: 128
    Designated Bridge: 0000.0000.0000.0000
    Number of forward-transitions: 0
    Version: Per-VLAN Spanning Tree Protocol - Received None - Sent STP
    Portfast: off
    Configured Root guard: off; Operational Root guard: off
    Bpdu-guard: off
    Link-type: point-to-point
    Received BPDUs: 0; Sent BPDUs: 0

 Port Et 0/4 enabled
    Ifindex: 201359360; Id: 8002; Role: Disabled; State: Disabled
    Designated Path Cost: 0
    Configured Path Cost: 20000000
    Designated Port Id: 0; Port Priority: 128
    Designated Bridge: 0000.0000.0000.0000
    Number of forward-transitions: 0
    Version: Per-VLAN Spanning Tree Protocol - Received None - Sent STP
    Portfast: off
    Configured Root guard: off; Operational Root guard: off
    Bpdu-guard: off
    Link-type: point-to-point
    Received BPDUs: 0; Sent BPDUs: 0

VLAN 201

 Spanning-tree Mode: Rapid PVST Protocol

 Root Id: 30c9.01e0.5200.0180 (self)
 Bridge Id: 30c9.01e0.5200.0180

 Root Bridge Forward Delay: 15; Hello Time: 2; Max Age: 20; Max-hops: 20
 Configured Forward Delay: 20; Hello Time: 8; Max Age: 22; Max-hops: 20
 Tx-HoldCount 5
 Number of topology change(s): 0

 Bpdu-guard errdisable timeout: disabled
 Bpdu-guard errdisable timeout interval: 300 sec

 Port Et 0/3 enabled
    Ifindex: 201351168; Id: 8001; Role: Disabled; State: Disabled
    Designated Path Cost: 0
    Configured Path Cost: 20000000
    Designated Port Id: 0; Port Priority: 128
    Designated Bridge: 0000.0000.0000.0000
    Number of forward-transitions: 0
    Version: Per-VLAN Spanning Tree Protocol - Received None - Sent STP
    Portfast: off
    Configured Root guard: off; Operational Root guard: off
    Bpdu-guard: off
    Link-type: point-to-point
    Received BPDUs: 0; Sent BPDUs: 0

 Port Et 0/4 enabled
    Ifindex: 201359360; Id: 8002; Role: Disabled; State: Disabled
    Designated Path Cost: 0
    Configured Path Cost: 20000000
    Designated Port Id: 0; Port Priority: 128
    Designated Bridge: 0000.0000.0000.0000
    Number of forward-transitions: 0
    Version: Per-VLAN Spanning Tree Protocol - Received None - Sent STP
    Portfast: off
    Configured Root guard: off; Operational Root guard: off
    Bpdu-guard: off
    Link-type: point-to-point
    Received BPDUs: 0; Sent BPDUs: 0

VLAN 301

 Spanning-tree Mode: Rapid PVST Protocol

 Root Id: 512d.01e0.5200.0180 (self)
 Bridge Id: 512d.01e0.5200.0180

 Root Bridge Forward Delay: 15; Hello Time: 2; Max Age: 20; Max-hops: 20
 Configured Forward Delay: 20; Hello Time: 8; Max Age: 22; Max-hops: 20
 Tx-HoldCount 5
 Number of topology change(s): 0

 Bpdu-guard errdisable timeout: disabled
 Bpdu-guard errdisable timeout interval: 300 sec

 Port Et 0/3 enabled
    Ifindex: 201351168; Id: 8001; Role: Disabled; State: Disabled
    Designated Path Cost: 0
    Configured Path Cost: 20000000
    Designated Port Id: 0; Port Priority: 128
    Designated Bridge: 0000.0000.0000.0000
    Number of forward-transitions: 0
    Version: Per-VLAN Spanning Tree Protocol - Received None - Sent STP
    Portfast: off
    Configured Root guard: off; Operational Root guard: off
    Bpdu-guard: off
    Link-type: point-to-point
    Received BPDUs: 0; Sent BPDUs: 0

 Port Et 0/4 enabled
    Ifindex: 201359360; Id: 8002; Role: Disabled; State: Disabled
    Designated Path Cost: 0
    Configured Path Cost: 20000000
    Designated Port Id: 0; Port Priority: 128
    Designated Bridge: 0000.0000.0000.0000
    Number of forward-transitions: 0
    Version: Per-VLAN Spanning Tree Protocol - Received None - Sent STP
    Portfast: off
    Configured Root guard: off; Operational Root guard: off
    Bpdu-guard: off
    Link-type: point-to-point
    Received BPDUs: 0; Sent BPDUs: 0

Observe that the settings comply with the formula set out in the STP parameters section, as:

(2 × (forward delay - 1)) ≥ maximum age ≥ (2 × (hello time + 1))

or in this case: 28 ≥ 20 ≥ 6.

Save the configuration.

device# copy running-config startup-config

Enable R-PVST+ on a system configuration example

device# configure terminal
device(config)# protocol spanning-tree rpvst
device(config-rpvst)# bridge-priority 4096
device(config-rpvst)# forward-delay  20
device(config-rpvst)# hello-time 8
device(config-rpvst)# max-age 22
device(config-rpvst)# transmit-holdcount 5
device(config-rpvst)# vlan 100 priority 0
device(config-rpvst)# vlan 201 priority 12288
device(config-rpvst)# vlan 301 priority 20480
device(config-rpvst)# interface ethernet 0/3
device(conf-if-eth-0/3)# switchport
device(conf-if-eth-0/3)# switchport mode trunk
device(conf-if-eth-0/3)# switchport trunk allowed vlan add 100 
device(conf-if-eth-0/3)# switchport trunk allowed vlan add 201 
device(conf-if-eth-0/3)# switchport trunk allowed vlan add 301 
device(conf-if-eth-0/3)# no spanning-tree shutdown
device(conf-if-eth-0/3)# exit
device(config)# interface ethernet 0/4
device(conf-if-eth-0/4)# switchport
device(conf-if-eth-0/4)# switchport mode trunk
device(conf-if-eth-0/4)# switchport trunk allowed vlan add 100 
device(conf-if-eth-0/4)# switchport trunk allowed vlan add 201 
device(conf-if-eth-0/4)# switchport trunk allowed vlan add 301 
device(conf-if-eth-0/4)# no spanning-tree shutdown
device(conf-if-eth-0/4)# end
device# show spanning-tree 
device# copy running-config startup-config