Configuration procedure ···································································································································· 187
Configuration prerequisites ································································································································ 188
Configuration guidelines ···································································································································· 188
Configuration procedure ···································································································································· 189
Configuration example ······································································································································· 189
Configuring a 6to4 tunnel ··········································································································································· 193
Configuration prerequisites ································································································································ 193
Configuration guidelines ···································································································································· 193
Configuration procedure ···································································································································· 193
Configuration example ······································································································································· 194
Configuring an ISATAP tunnel ···································································································································· 196
Configuration prerequisites ································································································································ 196
Configuration guidelines ···································································································································· 197
Configuration procedure ···································································································································· 197
Configuration example ······································································································································· 198
Configuration prerequisites ································································································································ 200
Configuration guidelines ···································································································································· 200
Configuration procedure ···································································································································· 201
Configuration example ······································································································································· 201
Configuration prerequisites ································································································································ 205
Configuration guidelines ···································································································································· 205
Configuration procedure ···································································································································· 205
Configuration example ······································································································································· 206
Configuration prerequisites ································································································································ 209
Configuration guidelines ···································································································································· 209
Configuration procedure ···································································································································· 210
Configuration example ······································································································································· 211
Symptom ······························································································································································· 214
Solution ································································································································································· 214
Configuring GRE ····················································································································································· 216
Overview ······································································································································································· 216
GRE encapsulation format ·································································································································· 216
Protocols and standards ····································································································································· 218
Configuration prerequisites ································································································································ 218
Configuration guidelines ···································································································································· 218
Configuration procedure ···································································································································· 218
Configuration prerequisites ································································································································ 219
Configuration guidelines ···································································································································· 219
Configuration procedure ···································································································································· 220
Displaying and maintaining GRE ······························································································································· 221
Troubleshooting GRE ··················································································································································· 228
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