47Spanning Tree Protocol (STP)The spanning tree protocol (STP) is supported on the Z9000 platform.Protocol OverviewSTP is a Layer 2 protocol — specified by IEEE 802.1d — that eliminates loops in a bridged topology byenabling only a single path through the network.By eliminating loops, the protocol improves scalability in a large network and allows you to implementredundant paths, which can be activated after the failure of active paths. Layer 2 loops, which can occurin a network due to poor network design and without enabling protocols like xSTP, can causeunnecessarily high switch CPU utilization and memory consumption.Dell Networking OS supports three other variations of spanning tree, as shown in the following table.Table 53. Dell Networking OS Supported Spanning Tree ProtocolsDell Networking Term IEEE SpecificationSpanning Tree Protocol (STP) 802.1dRapid Spanning Tree Protocol (RSTP) 802.1wMultiple Spanning Tree Protocol (MSTP) 802.1sPer-VLAN Spanning Tree Plus (PVST+) Third PartyConfigure Spanning TreeConfiguring spanning tree is a two-step process.• Configuring Interfaces for Layer 2 Mode• Enabling Spanning Tree Protocol GloballyRelated Configuration Tasks• Adding an Interface to the Spanning Tree Group• Modifying Global Parameters• Modifying Interface STP Parameters• Enabling PortFast• Prevent Network Disruptions with BPDU Guard• STP Root Guard• Enabling SNMP Traps for Root Elections and Topology Changes• Configuring Spanning Trees as HitlessSpanning Tree Protocol (STP) 779
