Dell PowerSwitch S4128F-ON EMC SmartFabric OS10 User Guide Release 10.5.0 - Page 669

Fast convergence Fast convergence sets the minimum origination and arrival LSA parameters to zero (0), allowing rapid route calculation. A higher convergence level can result in occasional loss of OSPF adjacency. Convergence level 1 meets most convergence requirements. The higher the number, the faster the convergence, and the more frequent the route calculations and updates. This impacts CPU utilization and may impact adjacency stability in larger topologies. NOTE: Select higher convergence levels only after checking with Dell EMC Technical Support. When you disable fast-convergence, origination and arrival LSA parameters are set to 0 msec and 1000 msec, respectively. Setting the convergence parameter from 1 to 4 indicates the actual convergence level. Each convergence setting adjusts the LSA parameters to zero, but the convergence-level parameter changes the convergence speed. The higher the number, the faster the convergence. • Enable OSPFv2 fast-convergence and enter the convergence level in ROUTER-OSPF mode, from 1 to 4. fast-converge convergence-level Configure fast convergence OS10(config)# router ospf 65535 OS10(conf-router-ospf-65535)# fast-converge 1 View fast convergence OS10(conf-router-ospf-65535)# do show ip ospf Routing Process ospf 65535 with ID 99.99.99.99 Supports only single TOS (TOS0) routes It is an Autonomous System Border Router It is an Area Border Router It is Flooding according to RFC 2328 Convergence Level 1 Min LSA origination 0 msec, Min LSA arrival 0 msec Min LSA hold time 0 msec, Max LSA wait time 0 msec Number of area in this router is 3, normal 1 stub 1 nssa 1 Area BACKBONE (0) Number of interface in this area is 1 SPF algorithm executed 28 times Area ranges are Area (2) Number of interface in this area is 1 SPF algorithm executed 28 times Area ranges are Area (3) Number of interface in this area is 1 SPF algorithm executed 28 times Area ranges are Disable fast convergence OS10(conf-router-ospf-65535)# no fast-converge Interface parameters To avoid routing errors, interface parameter values must be consistent across all interfaces. For example, set the same time interval for the hello packets on all routers in the OSPF network to prevent misconfiguration of OSPF neighbors. 1. To change the OSPFv2 parameters in CONFIGURATION mode, enter the interface. interface interface-name 2. Change the cost associated with OSPF traffic on the interface in INTERFACE mode, from 1 to 65535. The default depends on the interface speed. ip ospf cost Layer 3 669