Description:
This document describes the information that needs to be collected in order for our Support to determine the cause of this behavior.
This article describes how to troubleshoot problems with a VPN connection between two routers. How to troubleshoot a problematic VPN connection when using the Advanced VPN Client is described in this Knowledge Base article.
Requirements:
- LCOS as of version 9.20 (download latest version)
- LANtools as of version 9.20 (download latest version)
Procedure:
Generating traces on a LANCOM router:
1) Using the LANtracer, connect to the affected router and load the attached trace configuration into the trace module.
If this is a VPN connection between two LANCOM routers, the traces must be created on both routers at the same time.
Important:
The traces must be created locally and not via the VPN connection, as otherwise important information will be lost if the connection is broken!
The procedure for creating traces using a ready-made trace configuration is described in this Knowledge-Base article.
2) If several VPN connections terminate on the router, the VPN-IKE trace must be filtered for the public IP address of the other VPN participant by means of the Filter field.
Info:
If the other VPN subscriber has a dynamic IP address and can be reached at a DynDNS address, enter the currently assigned IP address.
Important:
Only the VPN-IKE trace should be filtered.
3) Start the trace by clicking the button with the green arrow and record the occurrence of the error.
Important:
The trace must include the attempt to connect and/or the termination.
4) Stop the trace by clicking on the button with the stop sign and save it.
Collecting information from routers from other manufacturers:
If one of the two routers is a device from another manufacturer, we need the following information from this device:
- VPN configuration in text form or screenshots
- VPN debug information, which documents the behavior of the device. These must be created at the same time as the trace of the LANCOM router.
