Configuring a virtual link ······································································································································ 75
Configuring OSPF network types ································································································································· 76
Configuration prerequisites ·································································································································· 76
Configuring OSPF route control ··································································································································· 78
Configuration prerequisites ·································································································································· 78
Configuring OSPF preference ······························································································································ 82
Advertising a host route ········································································································································ 84
Configuration prerequisites ·································································································································· 84
Configuring OSPF packet timers ·························································································································· 84
Configuring stub routers ······································································································································· 87
Configuring OSPF authentication ························································································································ 88
Logging neighbor state changes ·························································································································· 89
Enabling message logging ··································································································································· 90
Enabling OSPF ISPF ·············································································································································· 92
Configuring OSPF FRR ··················································································································································· 92
Configuring the OSPF GR Helper ························································································································ 95
Configuring BFD for OSPF ············································································································································ 96
Displaying and maintaining OSPF ······························································································································· 96
OSPF configuration examples ······································································································································ 98
Configuring an OSPF stub area························································································································· 105
Configuring an OSPF NSSA area ····················································································································· 107
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