Reference Guide

890 | Spanning Tree Protocol (STP)
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Dell Networking OS supports three other variations of Spanning Tree, as shown here:
Configuring Spanning Tree
Configuring Spanning Tree is a two-step process:
1. Configuring Interfaces for Layer 2 Mode.
2. Enabling Spanning Tree Protocol Globally.
Related Configuration Tasks
• Adding an Interface to the Spanning Tree Group
• Removing an Interface from the Spanning Tree Group
• Modifying Global Parameters
• Modifying Interface STP Parameters
• Enabling PortFast
• Preventing Network Disruptions with BPDU Guard
• BPDU Filtering
• SNMP Traps for Root Elections and Topology Changes
• Configuring Spanning Trees as Hitless
Important Points to Remember
• Spanning Tree Protocol (STP) is disabled by default.
• Dell Networking OS supports only one Spanning Tree instance (0). For multiple instances, you must
enable MSTP, or PVST+. You may only enable one flavor of Spanning Tree at any one time.
• All ports in VLANs and all enabled interfaces in Layer 2 mode are automatically added to the
Spanning Tree topology at the time you enable the protocol.
• To add interfaces to the Spanning Tree topology after STP is enabled, enable the port and configure it
for Layer 2 using the command switchport.
• The IEEE Standard 802.1D allows eight bits for port ID and eight bits for priority. The eight bits for
port ID provide port IDs for 256.
Table 50-1. Dell Networking OS Supported Spanning Tree Protocols
Dell Networking Term IEEE Specification
Spanning Tree Protocol (STP) 802.1d
Rapid Spanning Tree Protocol
(RSTP)
802.1w
Multiple Spanning Tree Protocol
(MSTP)
802.1s
Per-VLAN Spanning Tree Plus
(PVST+)
Third Party