Configuring OSPF preference ······························································································································ 83
Advertising a host route ········································································································································ 85
Configuration prerequisites ·································································································································· 86
Configuring OSPF packet timers ·························································································································· 86
Configuring stub routers ······································································································································· 89
Configuring OSPF authentication ························································································································ 89
Logging neighbor state changes ·························································································································· 91
Enabling message logging ··································································································································· 92
Enabling OSPF ISPF ·············································································································································· 93
Configuring OSPF FRR ··················································································································································· 93
Configuring the OSPF GR Helper ························································································································ 96
Configuring BFD for OSPF ············································································································································ 97
Displaying and maintaining OSPF ······························································································································· 98
OSPF configuration examples ······································································································································ 99
Configuring an OSPF stub area························································································································· 107
Configuring an OSPF NSSA area ····················································································································· 109
Configuring OSPF DR election ··························································································································· 111
Configuring OSPF virtual links ··························································································································· 115
Configuring route filtering ·································································································································· 120
Configuring OSPF FRR ········································································································································ 122
Configuring BFD for OSPF ································································································································· 124
Incorrect routing information ······························································································································ 129
IS-IS configuration ··················································································································································· 130
IS-IS overview ······························································································································································· 130
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