OSPF GR configuration example ······················································································································· 113
OSPF FRR configuration example ······················································································································ 118
Incorrect routing information ······························································································································ 120
Configuring IS-IS ····················································································································································· 122
Overview ······································································································································································· 122
Terminology ························································································································································· 122
IS-IS address format ············································································································································· 122
NET ······································································································································································· 123
IS-IS area ······························································································································································ 124
IS-IS network types ·············································································································································· 126
IS-IS PDUs ····························································································································································· 127
Protocols and standards ····································································································································· 128
IS-IS configuration task list ··········································································································································· 129
Configuring basic IS-IS ················································································································································ 130
Configuration prerequisites ································································································································ 130
Enabling IS-IS ······················································································································································· 130
Configuring IS-IS route control ···································································································································· 132
Configuration prerequisites ································································································································ 132
Configuring IS-IS link cost ··································································································································· 132
Advertising a default route ································································································································· 134
Configuring IS-IS route leaking ·························································································································· 136
Configuration prerequisites ································································································································ 137
Configuring LSP parameters ······························································································································· 140
Setting the LSDB overload bit ····························································································································· 144
Enabling IS-IS ISPF ··············································································································································· 146
Enhancing IS-IS network security ································································································································ 147
Configuration prerequisites ································································································································ 147
Configuring area authentication ························································································································ 147
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