OSPF GR configuration example ······················································································································· 115
OSPF NSR configuration example ···················································································································· 117
OSPF FRR configuration example ······················································································································ 122
Incorrect routing information ······························································································································ 124
Configuring IS-IS ····················································································································································· 126
Overview ······································································································································································· 126
Terminology ························································································································································· 126
IS-IS address format ············································································································································· 126
NET ······································································································································································· 127
IS-IS area ······························································································································································ 128
IS-IS network types ·············································································································································· 130
IS-IS PDUs ····························································································································································· 131
Protocols and standards ····································································································································· 132
IS-IS configuration task list ··········································································································································· 133
Configuring basic IS-IS ················································································································································ 134
Configuration prerequisites ································································································································ 134
Enabling IS-IS ······················································································································································· 134
Configuring IS-IS route control ···································································································································· 135
Configuration prerequisites ································································································································ 135
Configuring IS-IS link cost ··································································································································· 136
Advertising a default route ································································································································· 138
Configuring IS-IS route leaking ·························································································································· 140
Configuration prerequisites ································································································································ 141
Configuring LSP parameters ······························································································································· 143
Setting the LSDB overload bit ····························································································································· 146
Enabling IS-IS ISPF ··············································································································································· 148
Enhancing IS-IS network security ································································································································ 150
Configuration prerequisites ································································································································ 150
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