Contents 37Configuring L2 and L3 Relay Features (CLI) . . . . . . . 937Configuring L2 DHCP Relay . . . . . . . . . . . . . 937Configuring L3 Relay (IP Helper) Settings . . . . . 938Relay Agent Configuration Example . . . . . . . . . . 94034 Configuring OSPF and OSPFv3 . . . . . . . 943OSPF Overview . . . . . . . . . . . . . . . . . . . . . 944What Are OSPF Areas and Other OSPFTopology Features? . . . . . . . . . . . . . . . . . 944What Are OSPF Routers and LSAs? . . . . . . . . 945How Are Routes Selected? . . . . . . . . . . . . . 945How Are OSPF and OSPFv3 Different? . . . . . . . 945Default OSPF Values . . . . . . . . . . . . . . . . . . . 946Configuring OSPF Features (Web) . . . . . . . . . . . . 948OSPF Configuration . . . . . . . . . . . . . . . . . 948OSPF Area Configuration . . . . . . . . . . . . . . 949OSPF Stub Area Summary . . . . . . . . . . . . . 952OSPF Area Range Configuration . . . . . . . . . . 953OSPF Interface Statistics . . . . . . . . . . . . . . 954OSPF Interface Configuration . . . . . . . . . . . 955OSPF Neighbor Table . . . . . . . . . . . . . . . . 956OSPF Neighbor Configuration . . . . . . . . . . . 957OSPF Link State Database . . . . . . . . . . . . . 958OSPF Virtual Link Configuration . . . . . . . . . . 958OSPF Virtual Link Summary. . . . . . . . . . . . . 960OSPF Route Redistribution Configuration . . . . . 961OSPF Route Redistribution Summary. . . . . . . . 962NSF OSPF Summary (PCM6220 andPCM6348 Only) . . . . . . . . . . . . . . . . . . . 963
