Dell MX9116n EMC SmartFabric OS10 User Guide - Page 439

Interface Name Role PortID Prio Cost Sts Cost Link-type Edge ethernet1/1/1 Disb 128.260 128 200000000 BLK 0 AUTO No ethernet1/1/2 Disb 128.264 128 200000000 BLK 0 AUTO No ethernet1/1/3 Disb 128.268 128 200000000 BLK 0 AUTO No ethernet1/1/4 Disb 128.272 128 200000000 BLK 0 AUTO No ethernet1/1/5:1 Disb 128.276 128 200000000 BLK 0 AUTO No Global parameters The root bridge sets the values for forward-time, hello-time, and max-age, and overwrites the values set on other bridges participating in the RSTP group. NOTE: Dell EMC recommends that only experienced network administrators change the RSTP group parameters. Poorly planned modification of the RSTP parameters can negatively affect network performance. Forward-time Hello-time Max-age Port cost 15 seconds - Amount of time an interface waits in the Listening state and Learning state before it transitions to the Forwarding state. 2 seconds - Time interval in which the bridge sends RSTP BPDUs. 20 seconds - Length of time the bridge maintains configuration information before it refreshes that information by recomputing the RSTP topology. Port cost values to set the path cost of the interface: • 100-Mb/s Ethernet interfaces - 200000 • 1-Gigabit Ethernet interfaces - 20000 • 10-Gigabit Ethernet interfaces - 2000 • 40-Gigabit Ethernet interfaces - 500 • Port-channel with 100 Mb/s Ethernet interfaces - 200000 • Port-channel with 1-Gigabit Ethernet interfaces - 20000 • Port-channel with 10-Gigabit Ethernet interfaces - 2000 • Port-channel with 1x40Gigabit Ethernet interface - 500 • Port-channel with 2x40Gigabit Ethernet interfaces - 250 • Change the forward-time in CONFIGURATION mode, from 4 to 30, default 15. spanning-tree rstp forward-time seconds • Change the hello-time in CONFIGURATION mode, from 1 to 10, default 2. With large configurations, especially those configurations with more ports, Dell EMC recommends increasing the hello-time. spanning-tree rstp hello-time seconds • Change the max-age in CONFIGURATION mode, from 6 to 40, default 20. spanning-tree rstp max-age seconds View current interface parameters OS10# show spanning-tree active Spanning tree enabled protocol rstp with force-version rstp Executing IEEE compatible Spanning Tree Protocol Root ID Priority 32768, Address 90b1.1cf4.9b8a Root Bridge hello time 2, max age 20, forward delay 15 Bridge ID Priority 32768, Address 90b1.1cf4.9b8a We are the root Configured hello time 2, max age 20, forward delay 15 Interface Designated Name PortID Prio Cost Sts Cost Bridge ID PortID ethernet1/1/1 244.128 128 500 BLK 0 32768 90b1.1cf4.9b8a 128.244 ethernet1/1/2 248.128 128 500 BLK 0 32768 90b1.1cf4.9b8a 128.248 ethernet1/1/3 252.128 128 500 FWD 0 32768 90b1.1cf4.9b8a 128.252 ethernet1/1/4 256.128 128 500 BLK 0 32768 90b1.1cf4.9b8a 128.256 Layer 2 439