Users Guide

Table Of Contents
Supported
Releases
10.2.0E or later
Rapid per-VLAN spanning-tree
Rapid per-VLAN spanning-tree (Rapid-PVST) is used to create a single topology per VLAN. Rapid-PVST is enabled by default; it
provides faster convergence than STP and runs on the default VLAN (VLAN 1).
Configuring Rapid-PVST is a four-step process:
1. Ensure the interfaces are in L2 mode.
2. Place the interfaces in VLANs. By default, switchport interfaces are members of the default (VLAN1).
3. Enable Rapid-PVST. This step is only required if another variation of STP is present.
4. (Optional) Select a non-default bridge-priority for the VLAN for load balancing.
Each VLAN is assigned an incremental default bridge priority. For example, if VLAN 1 is assigned a bridge priority value of 32769,
then VLAN 2 (if created) is assigned a bridge priority value of 32770; similarly, VLAN 10 (if created) is assigned a bridge priority
value of 32778, and so on. All three instances have the same forwarding topology.
NOTE:
Z9332F-ON supports a total of 64 instances, of which 3 VLANs are used for internal purposes. When you run
Rapid-PVST flavor, each VLAN allocates one instance until the VLAN count reaches 61 and map the default instance after
that.
RSTP/MSTP/Rapid-PVST Force Version
RSTP/MSTP/Rapid-PVST is compatible and interoperable with the Spanning Tree Algorithm and Protocol (STP). An
administrative Force Protocol Version parameter allows you to emulate the behavior of the previous versions of the spanning
tree protocol that are not required for interoperability. The parameter applies to all the Bridge Ports.
Force protocol version in RSTP
Spanning-tree RSTP force-version (STP)
Setting the force version to STP forces the RSTP protocol to operate in 802.1D STP mode instead of the default protocol
mode, RSTP.
If the force version is STP, the rapid transitions are disabled.
Default behavior is RSTP operation mode, which supports faster convergence.
Force protocol version in MSTP
Spanning-tree MST force-version (STP/RSTP)
Setting the force version to STP forces the MSTP protocol to operate in 802.1D STP mode instead of the default protocol
mode, MSTP.
If Force Protocol Version is STP, rapid transitions are disabled.
Setting the force version to RSTP forces the MSTP protocol to operate in 802.1w RSTP mode instead of the default
protocol mode, MSTP. In this mode, it transmits RST BPDU which skips the MSTI information.
Layer 2
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