Enabling VBST
Context
The VBST configuration takes effect only when VBST is enabled.
When VBST is enabled on a ring network, VBST immediately starts spanning tree calculation. Parameters such as the switch priority and port priority affect spanning tree calculation, and change of these parameters may cause network flapping. To ensure fast and stable spanning tree calculation, perform basic configurations on the switch and ports before enabling VBST.
The PV quantity is the number of VBST-enabled interfaces multiplied by the number of VLANs. If the PV quantity exceeds the specifications, the CPU usage may exceed the threshold. As a result, the switch cannot process tasks in a timely manner, protocol calculation is affected, and even the device cannot be managed by the NMS. The PV quantity supported by the device is as follows:
The CPU usage of VBST is in direct proportion to the PV quantity.
- The device supports a maximum of 16000 PV values.
- The number of PV values on a switch is the sum of PV values of cards installed on the switch.
- The number of PV values of a stack is the sum of PV values of member switches.
Procedure
- Run system-view
The system view is displayed.
- Run stp mode vbst
The working mode of the switch is set to VBST.
By default, the switch works in MSTP mode.
The VBST mode cannot be used with the STP/RSTP/MSTP mode.
- If 1:N (N>1) mapping between MSTIs and VLANs has been configured on the switch, the mapping must be deleted before changing the STP working mode to VBST.
- Run stp enable
Global STP is enabled.
- Run undo stp vlan vlan-id [ to vlan-id ] [ vlan-id [ to vlan-id ] ] &<1-9> disable
VBST is enabled in each VLAN.
By default, VBST is enabled in a VLAN.
VBST cannot be enabled in the control VLAN used by ERPS or Smart Link.
If VLAN mapping, MUX VLAN, or VLAN stacking is configured on an interface corresponding to the VLAN, VBST negotiation for this VLAN will fail.
- Run interface interface-type interface-number
The interface view is displayed.
- Run stp enable
STP is enabled on the interface.
By default, STP is enabled on each switch interface.
- Run commit
The configuration is committed.
