Dell S4048T - PVST+ Sample Configurations

To keep both ports in a Forwarding state, use extend system ID. Extend system ID augments the bridge ID
with a VLAN ID to differentiate BPDUs on each VLAN so that PVST+ does not detect a loop and both ports
can remain in a Forwarding state.
Figure 111. PVST+ with Extend System ID
• Augment the bridge ID with the VLAN ID.
PROTOCOL PVST mode
extend system-id
Example of Viewing the Extend System ID in a PVST+ Configuration
Dell(conf-pvst)#do show spanning-tree pvst vlan 5 brief
VLAN 5
Executing IEEE compatible Spanning Tree Protocol
Root ID Priority 32773, Address 0001.e832.73f7
Root Bridge hello time 2, max age 20, forward delay 15
Bridge ID Priority 32773 (priority 32768
sys-id-ext 5), Address 0001.e832.73f7
We are the root of Vlan 5
Configured hello time 2, max age 20, forward delay 15
PVST+ Sample Configurations
The following examples provide the running configurations for the topology shown in the previous
illustration.
Example of PVST+ Configuration (R1)
interface TenGigabitEthernet 1/22
no ip address
switchport
no shutdown
!
Per-VLAN Spanning Tree Plus (PVST+) 829