Adding eth0 to bridge kills pppoe connection

I’m sorry for reposting this, but I can’t believe such a basic question got no answers.

I have pppoe adsl connection which works fine until I add eth0 to a bridge. After that, I can’t connect to adsl.

This seems like basic functionality to me, so please help me get it to work or tell me why it doesn’t.

Thanks.

vekaz schrieb:
> I’m sorry for reposting this, but I can’t believe such a basic question
> got no answers.
>
> I have pppoe adsl connection which works fine until I add eth0 to a
> bridge. After that, I can’t connect to adsl.
>
> This seems like basic functionality to me, so please help me get it to
> work or tell me why it doesn’t.

Well, personally I would always run PPPoE on a router, not on a
work machine (client or server), and much more so if the network
is as complicated as to calling for constructs like bridging.
Anyway, PPPoE has got it’s name (Point to Point Protocol over
Ethernet) for a reason. It’s point to point, meaning it connects
two parties, not more. So combining it with bridging is sort of
contradictory, and certainly not basic functionality.

Perhaps you’d share some information on what you are trying to do.
I guess you are running some version of openSUSE (because of the
group you chose to post to) on a PC (really just a guess) with two
(or more?) network interfaces (otherwise bridging wouldn’t make
sense), one of which is connected to an ADSL modem. What is
connected to the other one, and what are you trying to achieve by
bridging the two?


Tilman Schmidt
Phoenix Software GmbH
Bonn, Germany

A reply! Thank you very much :slight_smile:

I use VirtualBox in OpenSuse 11 host, and connectivity with Windows XP guest is the only reason I need bridging. I can successfully set up a bridge and host and guest get networked, but then adsl is not working, so I don’t have internet access in either OS.

I remember vmware doing similar setup automatically, and everything worked fine. So, although it may not be basic functionality, it is something that is known to work, I guess…

Thank you for any suggestions on how to solve this.

edit: Sorry, forgot to give details. I bridge my (only) physical network card with a virtual one. My ADSL modem is Siemens SpeedStream 4100. Connection stops working the moment I add eth0 (physical card) to a bridge, no matter if the virtual card is also added to the bridge or not.

vekaz schrieb:
> I use VirtualBox in OpenSuse 11 host, and connectivity with Windows XP
> guest is the only reason I need bridging.

I do the same but without bridging. Internet connectivity from the
Windows guest works just fine with the default VirtualBox network
setting of “NAT”.

> I can successfully set up a
> bridge and host and guest get networked, but then adsl is not working,
> so I don’t have internet access in either OS.
>
> I remember vmware doing similar setup automatically, and everything
> worked fine. So, although it may not be basic functionality, it is
> something that is known to work, I guess…

All I can say is that PPPoE is a hack messing with Ethernet layer 2,
bridging is another hack also messing with Ethernet layer 2, so it
doesn’t surprise me at all if the two don’t play well with each
other.

You could start debugging it the usual way: start by looking in the
relevant log files to see what is happening, try to isolate the point
where it goes wrong (interface binding? PPPoE packet forwarding?)
and then try to tweak that point. Perhaps post the results of your
investigation here for help in interpreting them. Perhaps submit a
bug report for the component you think is the culprit (pppoe daemon,
Linux bridging code, VirtualBox, Windows).

But I’d really recommend that you give up on that nonstandard
configuration as it’s generally much less of a hassle to stay with
the defaults.

And there are many good reasons for getting a router instead of
running PPPoE directly on your working machine.

HTH
T.


Tilman Schmidt
Phoenix Software GmbH
Bonn, Germany

Thank you very much Tilman.
I think I’ll get a router…