FRITZ!Box 6840 LTE Service - Knowledge Base

FRITZ!Box 6840 LTE Service

No IP communication over VPN connection between two FRITZ!Box networks

Although a VPN connection is established, network devices in one FRITZ!Box network cannot access network devices or services in the other FRITZ!Box network. When a network device in the remote FRITZ!Box network is pinged, there is no reply.

Important:Some of the settings described here are only displayed if the advanced view is enabled in the user interface. The configuration procedure and notes on functions given in this guide refer to the latest FRITZ!OS

Simply proceed as described below. After each measure, check whether the issue persists.

1 Deleting static IP routes

If a static IP route is configured in one or both FRITZ!Box(es) that points to the IP network of the other FRITZ!Box, VPN communication is not reliable.

Delete all such static IP routes in both FRITZ!Boxes:

  1. Click "Home Network" in the FRITZ!Box user interface.
  2. Click "Home Network Overview" or "Network" in the "Home Network" menu.
  3. Click on the "Network Settings" tab.
  4. Click the "IPv4 Routes" button.
  5. In the table, disable or delete all entries where the IP network of the remote FRITZ!Box is entered in the "Network" column.

    Example:
    The remote FRITZ!Box uses the IP address 192.168.10.1 with the subnet mask 255.255.255.0. This means that no static route may be active for the IP network 192.168.10.0.

  6. Click "OK" to save the settings.

2 Configuring parental controls to allow Internet access

You cannot access devices in the remote FRITZ!Box network over the VPN connection if the FRITZ!Box parental controls restrict the devices' Internet access. Therefore, make sure that the respective devices are allowed to access the Internet:

  1. Click "Internet" in the FRITZ!Box user interface.
  2. Click "Filters" in the "Internet" menu.
  3. Click on the "Parental Controls" tab.
  4. Check whether Internet access has been restricted for the device you would like to access over VPN.
    • If the device has unrestricted access to the Internet:
      • Proceed with the following section.
    • If Internet access has been restricted or blocked for the device:
      • Configure the parental controls for the device so that it has unrestricted use of the Internet.

3 Configuring a network device as a DHCP client

4 Correcting the VPN settings

If you entered the IP address (xxx.xxx.xxx.1) as the "destination network" instead of entering the IP network (xxx.xxx.xxx.0) of the FRITZ!Box when configuring up the VPN connection, you can only access the remote FRITZ!Box itself over the VPN connection.

Example:
The FRITZ!Box uses the IP address 192.168.10.1 with the subnet mask 255.255.255.0. This means that the FRITZ!Box's IP network is 192.168.10.0.

In order to rule this out as the cause, reconfigure the VPN connection: