Enabling and configuring R-PVST+ globally

  1. Enter global configuration mode.
    device# configure terminal
    
  2. Enable R-PVST+.
    device(config)# protocol spanning-tree rpvst
    
  3. Configure the bridge priority for the common instance.
    device(config-rpvst)# bridge-priority 4096
    
    Valid priority values range from 0 through 61440 in multiples of 4096. Assigning a lower priority value indicates that the bridge might become root.
  4. Configure the forward delay parameter.
    device(config-rpvst)# forward-delay  20
    
  5. Configure the hello time parameter.
    device(config-rpvst)# hello-time 22
    
  6. Configure the maximum age parameter.
    device(config-rpvst)# max-age 8
    
  7. Set the transmit hold count for the bridge.
    device(config-rpvst)# transmit-holdcount 9
    
    This command configures the maximum number of BPDUs transmitted per second before pausing for 1 second. The range is 1 through 10. The default is 6.
  8. Return to privileged exec mode.
    device(config-rpvst)# end
    
  9. Verify the configuration.
    device# show spanning-tree brief
    VLAN 1
    
     Spanning-tree Mode: Rapid PVST Protocol
    
          Root ID      Priority 4096
                       Address 01e0.5200.0180
                       Hello Time 2, Max Age 7, Forward Delay 11
    
          Bridge ID    Priority 32769
                       Address 01e0.5200.0180
                       Hello Time 8, Max Age 22, Forward Delay 20, Tx-HoldCount 9
                       Migrate Time 3 sec
    
     Interface     Role  Sts  Cost       Prio  Link-type        Edge
     ---------------------------------------------------------------------
    

    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: 20 ≥ 7 ≥ 6.

  10. Save the configuration.
    device# copy running-config startup-config
    

R-PVST+ 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 22
device(config-rpvst)# max-age 8
device(config-rpvst)# transmit-holdcount 9
device(config-rpvst)# end
device# show spanning-tree brief
device# copy running-config startup-config

For more information about configuring parameters, see the section STP parameter configuration.