Configuring OSPF inbound route filtering ·········································································································· 81

Configuring ABR Type-3 LSA filtering ················································································································· 82

Configuring an OSPF cost for an interface ········································································································ 82

Configuring the maximum number of OSPF routes ··························································································· 83

Configuring the maximum number of load-balanced routes ············································································ 83

Configuring OSPF preference ······························································································································ 83

Configuring OSPF route redistribution ················································································································ 84

Advertising a host route ········································································································································ 85

Tuning and optimizing OSPF networks ························································································································ 85

Configuration prerequisites ·································································································································· 86

Configuring OSPF packet timers ·························································································································· 86

Specifying LSA transmission delay ······················································································································ 87

Specifying SPF calculation interval ······················································································································ 87

Specifying the LSA arrival interval ······················································································································· 87

Specifying the LSA generation interval ··············································································································· 88

Disabling interfaces from receiving and sending OSPF packets ······································································ 88

Configuring stub routers ······································································································································· 89

Configuring OSPF authentication ························································································································ 89

Adding the interface MTU into DD packets ········································································································ 90

Configuring the maximum number of external LSAs in LSDB ··········································································· 90

Enabling compatibility with RFC 1583 ··············································································································· 90

Logging neighbor state changes ·························································································································· 91

Configuring OSPF network management ··········································································································· 91

Enabling message logging ··································································································································· 92

Enabling the advertisement and reception of opaque LSAs ············································································· 92

Configuring OSPF to give priority to receiving and processing hello packets ··············································· 92

Configuring the LSU transmit rate ························································································································ 93

Enabling OSPF ISPF ·············································································································································· 93

Configuring OSPF FRR ··················································································································································· 93

Configuring OSPF Graceful Restart ······························································································································ 95

Configuring the OSPF GR Restarter ····················································································································· 95

Configuring the OSPF GR Helper ························································································································ 96

Triggering OSPF Graceful Restart ························································································································ 97

Configuring BFD for OSPF ············································································································································ 97

Configuring control packet bidirectional detection ··························································································· 97

Configuring echo packet single-hop detection ··································································································· 97

Displaying and maintaining OSPF ······························································································································· 98

OSPF configuration examples ······································································································································ 99

Configuring OSPF basic functions ······················································································································· 99

Configuring OSPF route redistribution ·············································································································· 103

Configuring OSPF to advertise a summary route ····························································································· 104

Configuring an OSPF stub area························································································································· 107

Configuring an OSPF NSSA area ····················································································································· 109

Configuring OSPF DR election ··························································································································· 111

Configuring OSPF virtual links ··························································································································· 115

Configuring OSPF Graceful Restart ··················································································································· 117

Configuring route filtering ·································································································································· 120

Troubleshooting OSPF configuration ························································································································· 128

No OSPF neighbor relationship established ···································································································· 128

Incorrect routing information ······························································································································ 129

IS-IS configuration ··················································································································································· 130

IS-IS overview ······························································································································································· 130

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