Dell S4820T, Configuration Manual

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Enabling PVST+
When you enable PVST+, Dell Networking OS instantiates STP on each active VLAN.
1. Enter PVST context.
PROTOCOL PVST mode
protocol spanning-tree pvst
2. Enable PVST+.
PROTOCOL PVST mode
no disable
Disabling PVST+
To disable PVST+ globally or on an interface, use the following commands.
• Disable PVST+ globally.
PROTOCOL PVST mode
disable
• Disable PVST+ on an interface, or remove a PVST+ parameter configuration.
INTERFACE mode
no spanning-tree pvst
Example of Viewing PVST+ Configuration
To display your PVST+ configuration, use the
show config
command from PROTOCOL PVST mode.
Dell_E600(conf-pvst)#show config verbose
!
protocol spanning-tree pvst
no disable
vlan 100 bridge-priority 4096
Influencing PVST+ Root Selection
As shown in the previous per-VLAN spanning tree illustration, all VLANs use the same forwarding
topology because R2 is elected the root, and all TenGigabitEthernet ports have the same cost.
The following per-VLAN spanning tree illustration changes the bridge priority of each bridge so that a
different forwarding topology is generated for each VLAN. This behavior demonstrates how you can use
PVST+ to achieve load balancing.
780
Per-VLAN Spanning Tree Plus (PVST+)