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Kraven2323
Staff
Staff

Created on ‎04-11-2022 01:52 PM Edited on ‎04-18-2025 03:13 AM By Moderator

Article Id 209005

Technical Tip: PPPoE-interface configuration for IPv4 and IPv6

Description This article describes how to use the config pppoe-interface to set up a PPPoE connection for both IPv4 and IPv6.
Scope Firmware v6.2 and above. 
Results

Port3 will be used in this example as the one connected to the ISP.

Scenario: Both IPv4 and IPv6 should have a connection via PPPoE.

The IPv6 address is received via DHCP over a PPPoE connection.

 

  1. Start by configuring pppoe-interface for the port 3 connected with the PPPoE:

 

config system pppoe-interface

    edit "PPPOE"

        set ipv6 enable            --> Enabling IPv6 option under the PPPoE interface.

        set device "port3"

        set username <username>

        set password <password>

    next

end

 

  1. Enable DHCPv6 under the PPPoE interface:

    config system interface
        edit "PPPOE"
            set mode pppoe            
            set type tunnel
                config ipv6
                    set ip6-mode dhcp      --> Enabling IPv6 DHCP client option under the PPPoE interface.
                    set interface "port3"
        next
    end

     

  2. A physical interface only has an IPv6 option enabled:

    config system interface
        edit "port3"            
            set type physical
                config ipv6
        next
    end

     

When configuring pppoe-interface, one can select the port using the command 'set device <port>'. After that, a sub-interface will appear.

 

Kraven2323_0-1649641423436.png

 

Check under the 'diagnose netlink interface list <pppoe>' for the newly created interface:

 

diagnose netlink interface list PPPOE

if=PPPOE family=00 type=512 index=23 mtu=1492 link=0 master=0
ref=30 state=start present fw_flags=0 flags=up p2p run noarp multicast
Qdisc=pfifo_fast
stat: rxp=527 txp=1219 rxb=727091 txb=250660 rxe=0 txe=0 rxd=0 txd=0 mc=0 collision=0 @ time=1649641676
re: rxl=0 rxo=0 rxc=0 rxf=0 rxfi=0 rxm=0
te: txa=0 txc=0 txfi=0 txh=0 txw=0
misc rxc=0 txc=0
input_type=0 state=3 arp_entry=0 refcnt=30

 

Starting FortiOS v7.4.7 and above PPPoE option is available on GUI by default. Also, configuration will be retained in case addressing mode is set to other modes then back to PPPoE.

 

image.png


Note:

PPPoE Interfaces do not support NPU Offload.

Certain ISPs require the configuration of a VLAN ID on PPPoE connections.
After configuring PPPoE over the wan interface it will automatically add a route in the routing table which means that it is not required to create a separate entry in the routing table.


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