How to Set Up PPPoE on OPNsense (Wizard, Manual Setup, and VLAN)

A Complete Guide for UK BT Fibre and Lab Environments

If you are trying to set up PPPoE on OPNsense and cannot find the PPPoE option on the WAN interface anymore, you are not doing anything wrong. The way PPPoE is configured changed in recent versions of OPNsense, and many older guides are now out of date.

This guide explains the new method and walks through three different ways to configure PPPoE:

1. Using the setup wizard (quickest and easiest)

2. Manual setup without VLAN

3. Manual setup when your ISP requires VLAN tagging (for example VLAN 101)

These steps work for UK BT fibre connections and also for lab environments using a PPPoE test server, such as FreeBSD with mpd.

Some of these steps are easier to see than describe, so if you prefer, the full video walkthrough is embedded below.

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Why PPPoE Was Moved from the WAN Interface

In older versions of OPNsense and in pfSense, you could configure PPPoE directly on the WAN interface by selecting it from a drop-down menu. This is no longer how it works.

PPPoE is not actually part of the physical network interface. It is a virtual point-to-point connection that runs on top of:

• a physical network card, or

• a VLAN interface, if your ISP requires tagging

To better match how FreeBSD builds the network stack, OPNsense now treats PPPoE as a device rather than an interface setting. This is why PPPoE is now created under:

Interfaces → Devices → Point-to-Point

and then assigned to WAN afterwards.

The correct order is now:

Physical interface → (optional VLAN) → PPPoE device → assigned as WAN

Once PPPoE is assigned to WAN, all firewall rules, NAT, and routing use the PPPoE interface, not the physical network card.

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Method 1: Setting Up PPPoE Using the Setup Wizard

This is the simplest method and is suitable for most home users.

Step 1: Start the Wizard

After a fresh install, the setup wizard usually appears automatically. If not, it can be started from the dashboard.

Follow the wizard until you reach the WAN configuration step.

Step 2: Select PPPoE

When asked for the WAN connection type, select PPPoE.

Enter your username and password:

• BT Home Fibre usually uses something like:
  bthomehub@btbroadband.com

• BT Business Fibre usually uses something like:
  btbusinesshub@business.btclick.com

Important Note for BT Business Customers (Static IP Addresses)

If you are using BT Business broadband with a static IP address, it is very important that you use the correct business PPPoE username and password from above and not the home user credentials.

If you use the wrong credentials:

• the PPPoE connection may still come up,

• but you may be placed into a dynamic address pool, and

• you will not receive your assigned static IP address.

Step 3: Finish the Wizard

Complete the remaining steps and apply the configuration.

Step 4: Check What the Wizard Created

After the wizard finishes:

• Go to Interfaces → Devices → Point-to-Point
  You should see a PPPoE device listed (usually called pppoe0).

• Go to Interfaces → Assignments
  WAN should now be assigned to the PPPoE device, not to the physical network card.

This confirms the wizard has used the new PPPoE device method correctly.

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Method 2: Manual PPPoE Setup (No VLAN Required)

This method is useful if you want to understand exactly what is happening or if you are working in lab or MSP environments.

Step 1: Disable the Physical WAN Interface

Go to Interfaces → WAN (this is still the physical interface at this point).

Set:

• IPv4 Configuration Type: None

• IPv6 Configuration Type: None

• Untick Enable Interface

Save and apply changes.

This ensures the physical interface is only used as a carrier for PPPoE and not as a routed interface.

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Step 2: Create the PPPoE Device

Go to Interfaces → Devices → Point-to-Point and click Add.

Set:

• Link Type: PPPoE

• Parent Interface: select your physical WAN network card

Enter your PPPoE username and password.

Leave MTU and MRU blank unless you have a specific problem you are troubleshooting. Modern fibre connections negotiate this correctly.

Save the configuration.

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Step 3: Assign the PPPoE Device to WAN

Go to Interfaces → Assignments.

In the available interfaces drop-down list, select your PPPoE device (for example pppoe0) and click Add.

Assign this interface to WAN.

From this point onwards:

• WAN is now the PPPoE device

• The physical interface is no longer used directly by the firewall

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Step 4: Configure the WAN Interface

Go to Interfaces → WAN again.

Now you are editing the PPPoE interface, not the physical NIC.

Set:

• Enable Interface: checked

• IPv4 Configuration Type: None

• IPv6 Configuration Type: None (unless you are configuring IPv6 over PPPoE)

Leave MTU and MSS settings untouched.

The option Prevent interface removal only stops accidental deletion in the web interface. It does not affect how PPPoE works and can be left unticked.

Save and apply changes.

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Optional: Remove the Physical Interface Assignment

Once PPPoE is working, the physical interface does not need to remain assigned.

You may unassign it under Interfaces → Assignments unless you need it for:

• creating VLANs later

• MAC address cloning

• packet capture and troubleshooting

Removing it keeps the interface list clean and avoids confusion.

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Method 3: Manual PPPoE Setup When VLAN Is Required

Some ISPs require VLAN tagging before PPPoE will work. A common example is VLAN 101.

In this case, the stack becomes:

Physical interface → VLAN → PPPoE → WAN

Step 1: Disable the Physical WAN Interface

As before:

• Set IPv4 and IPv6 to None

• Disable the interface

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Step 2: Create the VLAN Interface

Go to Interfaces → Devices → VLAN and click Add.

Set:

• Parent Interface: your physical WAN NIC

• VLAN Tag: for example 101

Save the VLAN.

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Step 3: Create PPPoE on Top of the VLAN

Go to Interfaces → Devices → Point-to-Point and click Add.

Set:

• Link Type: PPPoE

• Parent Interface: select the VLAN you just created

Enter your PPPoE credentials and save.

Now PPPoE is running on top of the VLAN instead of directly on the physical port.

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Step 4: Assign PPPoE to WAN

Go to Interfaces → Assignments.

Assign the PPPoE interface to WAN.

At this point:

• Physical NIC carries VLAN traffic

• VLAN carries PPPoE

• PPPoE is the WAN interface used by the firewall

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NAT, Firewall Rules, and MSS Settings

When WAN is assigned to the PPPoE device, OPNsense automatically:

• applies firewall rules to the correct interface

• uses PPPoE for routing

• performs outbound NAT through the PPPoE interface

As long as outbound NAT is set to Automatic (default), no manual NAT rules are required.

TCP MSS does not need to be configured manually for PPPoE in most modern fibre setups. MTU is negotiated on the PPP link and Path MTU Discovery handles the rest. MSS clamping should only be used if you are fixing a specific problem.

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Common Problems

If PPPoE does not connect, check the following:

• Username format is correct (BT Home and BT Business use different domains)

• Correct parent interface or VLAN is selected

• PPPoE device is assigned to WAN

• Physical interface is not still configured as WAN

Authentication failures will appear in PPP logs under System → Log Files → General.

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Summary

Modern versions of OPNsense no longer configure PPPoE directly on the WAN interface. Instead:

• PPPoE is created as a Point-to-Point device

• That device is then assigned to WAN

Once you understand this model, both simple home setups and advanced ISP VLAN setups follow the same basic pattern.

Whether you use the wizard or configure everything manually, the important part is knowing where PPPoE now lives and how it fits into the network stack.