Reference Guide

786 | Per-VLAN Spanning Tree Plus
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FTOS supports three other variations of Spanning Tree, as shown in Table 43-1, "FTOS Supported
Spanning Tree Protocols," in Per-VLAN Spanning Tree Plus.
Implementation Information
• The FTOS implementation of PVST+ is based on IEEE Standard 802.1d.
• The FTOS implementation of PVST+ uses IEEE 802.1s costs as the default costs (Table 43-2,
"PVST+ Default Port Cost Values," in Per-VLAN Spanning Tree Plus). Other implementations use
IEEE 802.1d costs as the default costs if you are using Dell Force10 systems in a multi-vendor
network, verify that the costs are values you intended.
• You must allocate at least the default minimum amount of Layer 2 ACL CAM space when employing
PVST+ on the E-Series. Refer to Configure Ingress Layer 2 ACL Sub-partitions.
• On the C-Series and S-Series, you can enable PVST+ on 254 VLANs.
Configure Per-VLAN Spanning Tree Plus
Configuring PVST+ is a four-step process:
1. Configure interfaces for Layer 2.
2. Place the interfaces in VLANs.
3. Enable PVST+.
4. Optionally, for load balancing, select a non-default bridge-priority for a VLAN. Refer to Influence
PVST+ Root Selection.
Related Configuration Tasks
• Modify Global PVST+ Parameters
• Modify Interface PVST+ Parameters
• Configure an EdgePort
• Flush MAC Addresses after a Topology Change
• Preventing Network Disruptions with BPDU Guard
• Configuring Spanning Trees as Hitless
• PVST+ in Multi-vendor Networks
• PVST+ Extended System ID
• PVST+ Sample Configurations
Table 43-1. FTOS Supported Spanning Tree Protocols
Dell Force10 Term IEEE Specification
Spanning Tree Protocol 802.1d
Rapid Spanning Tree Protocol 802.1w
Multiple Spanning Tree Protocol 802.1s
Per-VLAN Spanning Tree Plus Third Party