How to Access a DSL Modem on a PPPoE WAN Connection?


#1

Here is a useful feature to allow access to your modem (if your modem supports it) when you are configuring your WAN with PPPoE.

When you use a modem that offers features that are still fully accessible when the modem is running in bridge mode (such as its entire web management interface being still accessible from the LAN port of the modem) you may find this hidden Peplink feature useful.

Background

Some DSL/ADSL/VDSL/Cable/Fibre modems allow you to configure it with a static IP, for the sake of this discussion, lets make it 192.168.100.1/24, now with the modem in Bridge mode and if we set the wired network port of your computer to a static IP in the same subnet, say 192.168.100.3/24 then the web admin interface of the router is accessible, giving access to very use useful diagnostic information and letting you confirm the modem is working before connecting to your router. Now if we connect the modem to the WAN port and configure that WAN port to PPPoE we can authenticate through the modem to the ISP successfully so we know our internet connection is working.

The question then is how do we access to the web access page of the modem without disconnecting the modem from the WAN and connecting the computer like above.

Solution

Peplink's engineers have hidden a very useful feature on the WAN configuration page, to find it, click on the blue (?) to the left of the text "IP Address (Optional)", this will reveal the text "To configure PPPoE management IP Address for access PPPoE modem, please click here", click on the "here" and the hidden option of "Management IP Address" will appear. Now in here enter a IP in the same subnet as your modem such as in this example 192.168.100.254 (not the IP of your modem). Save and Apply and you now from the LAN side of your Peplink router have access to the modems web interface again.

This feature is really helpful for in support cases you need to help a customer remotely diagnose a connection issues, we have done this by connecting into the customer network via a secondary connection (such as a LTE fail over) allowing us to work with the customer and the ISP to isolate the issue often minimising the need to attend site.

When the customer has a DSL Internet link, the DSL modem will be configured in bridge mode and it will be connected to Peplink WAN interfaces configured as PPPoE.

The following steps will enable users to access the admin page of the DSL modem.

Example Setup

- Balance 380 (WAN1 with PPPoE Connection Method) ➡ DSL Modem ➡ Internet
  • Modem IP = 192.168.10.1, Mask = 255.255.255.0

Accessing the WAN modem when the WAN port is configured as PPPoE

1. Navigate to Network > WAN > WAN1 > PPPoE Settings.

  1. Configure Management IP


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