Dell C1048P Port Extender Networking Configuration Guide for the C9000 Series - Page 1074
Spanning Tree Protocol (STP), Protocol Overview, Preventing Network Disruptions with BPDU Guard
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54 Spanning Tree Protocol (STP) The spanning tree protocol (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. 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 • Preventing Network Disruptions with BPDU Guard • Selecting STP Root • STP Root Guard • Enabling SNMP Traps for Root Elections and Topology Changes • STP Loop Guard • Displaying STP Guard Configuration Protocol Overview By eliminating loops, STP 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. The system supports three other versions of spanning tree, as shown in the following table. Table 87. 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 Spanning Tree Protocol (STP) 1074
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-
1,207
-
1,208
-
1,209
-
1,210
-
1,211
-
1,212
-
1,213
-
1,214
-
1,215
-
1,216
-
1,217
-
1,218
-
1,219
-
1,220
-
1,221
-
1,222
-
1,223
-
1,224
-
1,225
-
1,226
-
1,227
-
1,228
-
1,229
-
1,230
-
1,231
-
1,232
-
1,233
-
1,234
-
1,235
-
1,236
-
1,237
-
1,238
-
1,239
-
1,240
-
1,241
-
1,242
-
1,243
-
1,244
-
1,245
-
1,246
-
1,247
-
1,248
-
1,249
-
1,250
-
1,251