Network Router User Manual

ManualsBrandsPanasonic ManualsNetwork RouterNN46240-710

Nortel Secure Router 8000 Series

Troubleshooting - VPN

Issue 5.3 (19 January 2009)

Nortel Networks Inc.

Contents

About this document.......................................................................................................................1

1 L2TP troubleshooting................................................................................................................1-5

1.1 L2TP overview............................................................................................................................................1-5

1.1.1 Two typical L2TP tunnel modes........................................................................................................1-5

1.1.2 L2TP tunnel session setup.................................................................................................................1-5

1.2 VPDN troubleshooting on the L2TP ...........................................................................................................1-5

1.2.1 Networking environment...................................................................................................................1-5

1.2.2 Configuration notes...........................................................................................................................1-5

1.2.3 Diagnostic flowchart .........................................................................................................................1-5

1.2.4 Troubleshooting procedures ..............................................................................................................1-5

1.3 Troubleshooting L2TP access to the Layer 3 VPN......................................................................................1-5

1.3.1 Networking environment...................................................................................................................1-5

1.3.2 Configuration notes...........................................................................................................................1-5

1.3.3 Diagnostic flowchart .........................................................................................................................1-5

1.3.4 Troubleshooting procedure................................................................................................................1-5

1.4 Troubleshooting cases .................................................................................................................................1-5

1.4.1 The session disconnects as soon as it is set up ..................................................................................1-5

1.5 FAQs............................................................................................................................................................1-5

1.6 Diagnostic tools...........................................................................................................................................1-5

1.6.1 Display commands............................................................................................................................1-5

1.6.2 Debugging commands.......................................................................................................................1-5

2 GRE troubleshooting.................................................................................................................2-1

2.1 GRE overview.............................................................................................................................................2-2

2.1.1 Introduction to GRE..........................................................................................................................2-2

2.1.2 Related concepts of GRE ..................................................................................................................2-2

2.1.3 Applications of GRE .........................................................................................................................2-3

2.2 Troubleshooting GRE..................................................................................................................................2-4

2.2.1 Typical networking............................................................................................................................2-4

2.2.2 Configuration notes...........................................................................................................................2-4

2.2.3 Troubleshooting flowchart ................................................................................................................2-7

2.2.4 Troubleshooting procedure................................................................................................................2-8