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 From:  Fred Wright <fw at well dot com>
 To:  m0n0wall at lists dot m0n0 dot ch
 Subject:  Re: [m0n0wall] trouble connecting via pppoe still :(
 Date:  Thu, 19 Aug 2004 18:54:30 -0700 (PDT)
On Thu, 19 Aug 2004, [|] wrote:

> I made a post in the past detailing some trouble i am having connecting
> to my ISP via pppoe.
> my original post and the various replies can be read here:
> http://m0n0.ch/wall/list/query.php?query=trouble+connecting+via+pppoe&type=subj&Submit=Search
> Here is a brief rehash of the situation:
> m0n0wall is up and running currently connected to my ISP via static IP
> assignment
> I want to switch to connect to my ISP via pppoe because the newly
> available 3Mbit service is only available via a pppoe connection
> I am currently running m0n0wall 1.1b17
> I am currently running m0n0wall on a WRAP.1C-2 board
> My simple network diagram is like this:
> [Internet]--[DSL Modem]--[m0n0]--[switch]--[computers]
> My dsl modem is a Westel Wirespeed Model C90-36R516 Rev 8
> My dsl modem is just a dumb bridge according to my ISP
> My dsl modem's Ethernet port is connected to the correct interface on
> m0n0wall
> both the soekris and the wrap boards i tried have the latest bios installed
> Log files from m0n0wall can be found here:
> - http://n0t.net/m0n0wall.log.txt
> this log was the first failed attempt to connect via pppoe
> - http://n0t.net/m0n0wall1.log.txt
> this log was the second failed attempt to connect via pppoe after
> changing wires and upgrading from 1.0 to 1.1b14
> - http://n0t.net/m0n0wall2.log.txt
> this log was the third failed attempt to connect via pppoe after
> switching from m0n0wall on a soekris net4501 to a pcengines wrap board.
> during this attempt the ISP tech also switched from CHAP to PAP to
> troubleshoot. This can even be seen in the log. At first the m0n0wall
> tries to use CHAP and after the tech switched it tries to use PAP. This
> leads me to believe that the m0n0wall can see that the ISP changed the
> protocol but for some reason cannot complete the rest of the connection
> - i can connect via pppoe from a windows XP machine when i remove the
> m0n0wall and connect the dsl modem directly to the switch instead

This a "conspiracy bug", where *both* the client *and* the server are
misbehaving, and fixing either is probably sufficient.  What's happening
is that (assuming the log doesn't lie):

1) The server is trying to negotiate PPP Multilink, probably uselessly for
your single-link configuration. Hence the "MP MRRU" and "ENDPOINT DISC"

2) MPD is set up not to use multilink, and thus is rejecting
that.  However, due to a bug, it's *only* rejecting the "MP MRRU" option
and not the "ENDPOINT DISC" option.

3) The server is refusing to comply with the rejection, I suspect due to
the apparent acceptance of the "ENDPOINT DISC" option.  Thus, it simply
keeps trying the same request over and over again, while the client keeps
rejecting it over and over again.

The server's behavior is clearly the more illegal, since it's requesting
an option after it's been rejected.  But it would also be better if the
client rejected *all* multilink-related options when configured not to use
multilink.  The reason I suspect this is related is that otherwise the
server wouldn't work with *any* client that didn't support multilink.

ISTR another case failing in the other direction, where mon0wall's MPD was
requesting multilink and not handling the rejection properly (I think that
one was on PPTP).  Perhaps both bugs are in MPD. :-)

In theory, PPP is supposed to adjust to all combinations of settings by
having the two ends negotiate a mutually acceptable configuration.  In
practice, it doesn't always work that way due to coding bugs.

> Things i have not yet tried:
> I have not yet tried to use a different dsl modem. First of all i dont
> have easy access to another modem, i would have to purchase one.
> Secondly I am able to connect from Windows XP via pppoe through that
> same modem so the modem shouldn't be the issue in the first place.

And thirdly, you stated above that your modem is running in bridging mode,
which means that the PPPoE/PPP server is *not* in the modem.

> I have not yet tried to use software other than m0n0wall on either the
> wrap board or the net4501 such as StarOS or Microtik. what other
> softwares would you guys recommend i try? If other software can connect
> on the same hardware using pppoe without a problem what can i do to help

It's clearly a software problem, not a hardware problem.  It's also
clearly more at your ISP's end, though they may take the "anything that
works with Windows isn't broken" stance.  But fixing the MPD bug on the
m0n0wall side might make it work.

					Fred Wright