PPPoE Not Working

Hello, Just did a fresh install of ipfire 2.27 174 and PPPoE no longer connects. I did work fine in the last version of ipfire. I have tried it both bare metal and on proxmox with the same result. In the loga uder system RED I get thease enterys over and over. '17:38:12 pppd[13772]: PPPoE plugin from pppd 2.4.9
17:38:12 pppd[13772]: Plugin rp-pppoe.so loaded.
17:38:10 pppd[13654]: unrecognized option ‘20’
17:38:10 pppd[13654]: PPPoE plugin from pppd 2.4.9
17:38:10 pppd[13654]: Plugin rp-pppoe.so loaded.
17:38:10 pppd[13537]: unrecognized option ‘20’
17:38:10 pppd[13537]: PPPoE plugin from pppd 2.4.9
17:38:10 pppd[13537]: Plugin rp-pppoe.so loaded.
17:37:37 pppd[13175]: unrecognized option ‘20’ Is this a bug or am just missing somthing?

an MTU problem? I saw recently some post about that but I do not recollect which thread. Anyhow, according to chatGPT:

Option 20 is a PPPoE discovery packet option that is used to specify the maximum transmission unit (MTU) size of the Ethernet frame. This option is used to ensure that the size of the PPPoE packet is not too large for the network to handle.

The next sentence is a bit worrying, but I do not know if it is true:

If a PPPoE discovery packet with an unrecognized option 20 is received by the server or client, it means that the packet is not conforming to the PPPoE protocol and cannot be processed. The error message indicates that the option is not recognized, and the packet is likely to be dropped or ignored.

@bonnietwin or @bbitsch do you have any idea if this could be a problem?

Edit, few more info:

The error message “Plugin rp-pppoe.so loaded. Unrecognized option ‘20’” suggests that the PPPoE client is using the Roaring Penguin’s PPPoE plugin (rp-pppoe), and during the initialization process, it encounters an unrecognized or unsupported option with the value ‘20’. The rp-pppoe.so file is a shared library that enables PPPoE functionality in the PPP daemon (pppd).

Hi @cfusco , I am afraid I have no knowledge or experience about PPPoE.

I had a look through the commits and the last update to the ppp package was in April 2021.

A change was done to the pppsetup.cgi WUI page but that was in end of November 2022 and ended up in CU173.

I can’t find any changes that would be expected to impact PPPoE. (Doesn’t mean they aren’t there, just that I don’t recognise them).

Hi @jerry
Welcome to the IPFire community.

You mention that it was working fine in CU173 but you then did a fresh install of CU174. Is there a particular reason that you didn’t do an upgrade from CU173 to CU174 using Pakfire?

I would suggest re-installing CU173, confirm that you don’t have the problem and then do a Core Upgrade using Pakfire and see if it then works. If that then works it suggests that a bug crept in into the installer process but to confirm that you would need to do a freesh install of CU174 again and confirm that the problem returns.

If you can confirm that CU173 doesn’t have the problem and a fresh install and/or upgrade does have the problem then you should raise a bug for it.


Your IPFire people email address and password will act as your login credentials for the IPFire Bugzilla.

Hi, Yes CU173 was working fine. I did a fresh install to upgrade to a new SSD. I will reinstall CU173 and see if the problem persists.

FYI i have been using PPPoE for years and am using it on 2.27 CU 174 without problems.
Must be specific to your ISP connection.

1 Like

Hi everyone,
It was just me being stupid. I was cutting and pasting the the user and password instead of just typing them in. my apologias to the list for my own stupidly.
Thanks everyone who replied. I am stupid.
Regards Jerry


What is stupid is the error message, your action I would consider it absolutely normal. Great that you figure out the problem Thanks for letting us know.