Dell MX9116n EMC SmartFabric OS10 User Guide Release 10.5.1 - Page 539

1 100 2 200-300 Modify parameters The root bridge sets the values for forward-delay, hello-time, max-age, and max-hops and overwrites the values set on other MST bridges. Forward-time Hello-time Max-age Max-hops Time an interface waits in the Discarding state and Learning state before it transitions to the Forwarding state. Interval in which the bridge sends MST BPDUs. Length of time the bridge maintains configuration information before it refreshes that information by recomputing the MST topology. A maximum number of hops a BPDU travels before a receiving device discards it. NOTE: Dell EMC recommends that only experienced network administrators change MST parameters. Poorly planned modification of MST parameters can negatively affect network performance. 1. Change the forward-time parameter in CONFIGURATION mode, from 4 to 30, default 15. spanning-tree mst forward-time seconds 2. Change the hello-time parameter in CONFIGURATION mode, from 1 to 10, default 2. Dell EMC recommends increasing the hello-time for large configurations, especially configurations with more ports. spanning-tree mst hello-time seconds 3. Change the max-age parameter in CONFIGURATION mode, from 6 to 40, default 20. spanning-tree mst max-age seconds 4. Change the max-hops parameter in CONFIGURATION mode, from 1 to 40, default 20. spanning-tree mst max-hops number MST configuration OS10(config)# spanning-tree mst OS10(config)# spanning-tree mst forward-time 16 OS10(config)# spanning-tree mst hello-time 5 OS10(config)# spanning-tree mst max-age 10 OS10(config)# spanning-tree mst max-hops 30 View MSTP parameter values OS10# show spanning-tree active Spanning tree enabled protocol msti with force-version mst MSTI 0 VLANs mapped 1,31-4093 Executing IEEE compatible Spanning Tree Protocol Root ID Priority 32768, Address 3417.4455.667f Root Bridge hello time 2, max age 20, forward delay 15, max hops 20 Bridge ID Priority 32768, Address 90b1.1cf4.a523 Configured hello time 10, max age 40, forward delay 30, max hops 40 CIST regional root ID Priority 32768, Address 90b1.1cf4.a523 CIST external path cost 500 Interface Designated Name PortID Prio Cost Sts Cost Bridge ID PortID ethernet1/1/5 128.276 128 500 FWD 0 32768 3417.4455.667f 128.146 ethernet1/1/6 128.280 128 500 BLK 0 32768 3417.4455.667f 128.150 Interface Name Role PortID Prio Cost Sts Cost Link-type Edge ethernet1/1/5 Root 128.276 128 500 FWD 0 AUTO No ethernet1/1/6 Altr 128.280 128 500 BLK 0 AUTO No Layer 2 539