Dell S4048T User Manual

Spanning Tree Protocol (STP)
The spanning tree protocol (STP) is supported on Dell Networking OS.
Topics:
• Protocol Overview
• Configure Spanning Tree
• Important Points to Remember
• Configuring Interfaces for Layer 2 Mode
• Enabling Spanning Tree Protocol Globally
• Adding an Interface to the Spanning Tree Group
• Modifying Global Parameters
• Modifying Interface STP Parameters
• Enabling PortFast
• Selecting STP Root
• STP Root Guard
• Enabling SNMP Traps for Root Elections and Topology Changes
• Configuring Spanning Trees as Hitless
• STP Loop Guard
• Displaying STP Guard Configuration
Protocol Overview
STP is a Layer 2 protocol — specified by IEEE 802.1d — that eliminates loops in a bridged topology by
enabling only a single path through the network.
By eliminating loops, the protocol improves scalability in a large network and allows you to implement
redundant paths, which can be activated after the failure of active paths. Layer 2 loops, which can occur in a
network due to poor network design and without enabling protocols like xSTP, can cause unnecessarily high
switch CPU utilization and memory consumption.
Dell Networking OS supports three other variations of spanning tree, as shown in the following table.
Table 93. 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
54
Spanning Tree Protocol (STP) 1044

Dell S4048T Specifications

General

Switching Capacity	1.44 Tbps
Rack Units	1U
Form Factor	Rack-mountable
Power Device	Internal power supply
Power Redundancy	Optional
Product Type	Switch
Jumbo Frame Support	Yes
Routing Protocol	OSPF, BGP, RIP, VRRP, PIM-SM, IGMP
Remote Management Protocol	SNMP, RMON, Telnet, SSH
Features	Quality of Service (QoS), Jumbo Frames Support, Virtual Route Redundancy Protocol (VRRP), VLAN support, sFlow, Multiple Spanning Tree Protocol (MSTP), Rapid Spanning Tree Protocol (RSTP), IPv6 support
Compliant Standards	IEEE 802.3, IEEE 802.3u, IEEE 802.3ab, IEEE 802.3ae
Dimensions (W x D x H)	17.3 in x 16 in x 1.7 in
Operating Temperature	0°C to 40 °C
Operating Humidity	10% to 90% (non-condensing)