RPVST+ operating notes

Recommended application

RPVST+ is ideal in networks having less than 100 VLANs. In networks having 100 or more VLANs, MSTP is the recommended spanning tree choice due to the increased load on the switch CPU.

VLAN membership

A port will be part of a given VLAN spanning tree only if the port is a member of that VLAN.

RPVST+ interoperates with RSTP and MSTP on VLAN 1

Because a switch running RPVST+ transmits IEEE spanning tree BPDUs, it can interoperate with IEEE RSTP and MSTP spanning tree regions, and opens or blocks links from these regions as needed to maintain a loop-free topology with one physical path between regions.


RPVST+ interoperates with RSTP and MSTP only on VLAN 1.

Single spanning tree applications

One spanning tree variant can be run on the switch at any given time. On a switch running RPVST+, MSTP cannot be enabled. However, any MSTP-specific configuration settings in the startup configuration file will be maintained.


The following features cannot run concurrently with RPVST+:

  • Features that dynamically assign ports to VLANs:
    • GVRP

    • RADIUS-based VLAN assignments (802.1X, WebAuth, MKAC auth

    • Auth-VID/UnAuth-VID configuration on interfaces

    • MAC-Based VLANs

    • LLDP Radio Port VLAN

  • Switch Meshing

  • QinQ

  • Protocol VLANs

  • Distributed Trunking

  • Filter Multicast in rapid-PVST mode (The multicast MAC address value cannot be set to the PVST MAC address 01:00:0c:cc:cc:cd.)


Spanning tree mode cannot be set to RPVST+ when GVRP is enabled, and GVRP cannot be enabled when RPVST+ is enabled.

RPVST+ operating limits

Virtual ports (vPorts) on a switch are determined by the number of physical ports on the switch, plus other factors. Exceeding the recommended number of vPorts can result in dropped BPDUs.

Allowing traffic on per-VLAN ID (PVID) mismatched links

The switch generates an Event Log message for a VID mismatch on an active RPVST+ VLAN only if ignore-pvid-inconsistency is disabled (the default).

If ignore-pvid-inconsistency is enabled on multiple switches connected by hubs, there could be more than two VLANs involved in PVID mismatches that will be ignored by RPVST+.

If there is an actual misconfiguration of port VLAN memberships in a network, then enabling ignore-pvid-inconsistency prevents RPVST+ from detecting the problem. This could result in packet duplication in the network because RPVST+ would not converge correctly.