[isolated: see #91] PPPoE reconnect loop

[schnipp]

Hi all,

I am new here in this forum. First, I would like to thank all the guys involved in releasing Opnsense 18.1. You did a really great job. Unfortunately, I have a problem with my PPPoE connection on the WAN interface. I read a lot to get my problem solved, but no solution yet . Both in the Opnsense forum and some other FreeBSD forums similar problems are discussed, but I am not sure whether they are coincident.

After booting the system the PPPoE WAN connection works fine. But after interruption of the connection (e.g. dropping the connection after 24h like my ISP forces, other failures etc.) the system does not get a new stable PPPoE connection.

I tracked this issue down to packet capture. In general my ISP sends "PPP LCP echo request" packets every 10 seconds which the Opnsense answers immediately. But after interruption and reestablishing the PPPoE connection, the Opnsense does not answer incoming "PPP LCP echo request" packets anymore. After the fifth unanswered echo request my ISP drops the PPPoE connection. Afterwards the Opnsense tries to reconnect and runs in the infinite reconnection loop.

The only solution known to me is to reboot the system.

References:

• https://forum.opnsense.org/index.php?topic=4328.0
• https://forum.opnsense.org/index.php?topic=7003.0

[kug1977]

Hi,

I'm on OPNsense 18.1.2 and I'm facing the same problem. Solution so far is the cron reboot every day.

Kind regards,
Kay-Uwe

[schnipp]

Hi Kay-Uwe,

kann you tell me, what kinnd of configuration (e.g. modem) do you have on your WAN site?

I have a Fritzbox7412 in native bridge encapsulation mode and allow PPPoE passthrough. So the Opnsense sends PPPoE packet to the Fritzbox which encapsulates them into VLAN7 before forwarding to the BRAS.

[franco]

Do you guys have IPS enabled?


Cheers,
Franco

[elektroinside]

Heh
Just saw this.
@Franco, I guess I'm not alone

[schnipp]

Do you guys have IPS enabled?

Hi Franco,

currently, I have still a basic setup without IDS/IPS installed. Details of my setup…

• OPNsense 18.1.2_2
• Policy based routing (4 Ethernet interfaces)
• Mobile and LAN interconnected IPSec VPN
• 2 Dynamic DNS
• Inbound/Outbound NAT rules for using SIP-based VoIP
• DHCPv4, NTP and Unbound DNS (with forwarder)

Furthermore, I have to use a self-compiled NIC driver from Intel, because the NICs of my Board (Intel Atom C3000 Series; Supermicro A2SDi-4C-HLN4F) are not supported by FreeBSD 11.1. But the NICs themselves run seamlessly.

The next steps I want to try are…

• check PPPoE-forwarder of my DSL-Modem (Fritzbox 7412)
• extract mpd5 config and test with a vanilla FreeBSD 11.1 installation (Virtual Box)

Kind regards,
schnipp

[franco]

I was talking to another user today and we're handing out a custom kernel tomorrow to test a theory as we have one change that has not made it to FreeBSD yet...

https://reviews.freebsd.org/D9270


Cheers,
Franco

[glasi]

Hello all,

I just started with my own OPNsense setup and wanted to give some feedback.

So far everything works like a charm. Luckily, there are also no problems with PPPoE. On the WAN side I use the fiber optic bridge modem provided by my ISP Deutsche Telekom.

Regards,
glasi

[elektroinside]

Good to know some ISPs PPPoE link is ok, some are struggling
Thanks and welcome to OPNsense!

[elektroinside]

Btw, if you disconnect the WAN network cable and reconnect after a few seconds, is the PPPoE working again? If not, reboot to fix

[schnipp]

Today at midday my Internet stopped working and my Opnsense entered the infinite reconnection loop. Maybe my ISP initiated the termination of the connection (24 hour reconnection?)

Anyhow, it was a good moment to do some more investigation in that situation. So I did some packet captures in parallel on three network interfaces:

• WAN Interface of Opnsense (connected to 2.)
• ETH Interface of DSL-Modem (Fritzbox 7412, PPPoEx packet forwarding to 3. and vice versa)
• DSL Interface of DSL-Modem

Afterwards I rebooted the machine and in parallel started packet capturing of the two interfaces of the DSL-Modem.

Analyzing the capture files shows nothing really strange. The PPPoE packet forwarding between the modem interfaces looks fine. Only one reconfiguration request following a termination info from the ISP is not forwarded back to the Opnsense. This is ok, because there is no valid PPP-Session that moment.

The only difference in communication (1. connection after reboot and 2. reconnection loop) I can see is, that in the 2. case the Opnsense is not answering "LCP echo reply" packets sent by the ISP.

Presumably, there could be a timing issue or race condition somewhere in the PPPoE stack.

[elektroinside]

Perhaps this helps you as well, until this is fixed:
https://forum.opnsense.org/index.php?topic=7316.0

[kug1977]

Hi,

>Do you guys have IPS enabled?
No, not enabled.

>Btw, if you disconnect the WAN network cable and reconnect after a few seconds, is the PPPoE working again?
No, it needs a restart after.

Setup is:
Deutsche Telekom VDSL 50
Draytek Vigor 130 in PPPoE path-through /bridge mode
APU1D with OPNsense 18.1.2 on eth0

Kind regards,
Kay-Uwe

[elektroinside]

Well... I had a few adventures today with this. It has something to do with FreeBSD 11.1, because with OPNsense 17.7.12 if PPPoE is lost and then reconnected without a reboot, I get a new IPv4 - but IPv6 is lost.

With OPNsense 18.1 which is based on FreeBSD 11.1, only if I restart configd I get reconnected, but for some reason only for a few seconds.. then I get disconnected again and that's it, c'est fini until the next reboot.

So.. my automated method to reboot is the only thing that permanently brings back the PPPoE connection (so far).

[marjohn56]

With OPNsense 18.1 which is based on FreeBSD 11.1, only if I restart configd I get reconnected, but for some reason only for a few seconds.. then I get disconnected again and that's it, c'est fini until the next reboot.

Yet it does not affect all PPPoE users, me for example.