Re: Wired behaviour with IPv6 over PPP

From: James Chapman
Date: Thu May 22 2008 - 05:56:17 EST

Andrew Morton wrote:
On Wed, 21 May 2008 14:56:43 +0200 Matthias Cramer <matthias.cramer@xxxxxxxxxxx> wrote:

Hi All

I have a very wired behaviour when doing IPv6 over PPPoE.

The situation:

A linux box connected to a DSL Modem, on the other side is a Cisco LNS which terminates the PPP session (actually L2TP).
I have control over both ends.

When I have net.ipv6.conf.all.forwarding set to 0 then the ppp Interface gets a IPv6 address from the Cisco via IP6CP.
When I have net.ipv6.conf.all.forwarding set to 1 them the ppp Interface does not get an address, it has only a normal link local address.

What do you mean by normal link local address?

When I start the ppp session with forwarding set to 0 I can ping out and there exists a default route to ppp0 , then I switch forwarding to 1
the default route disappears and therefore routing does not work any longer.

Did this work with previous kernel versions?

Does pppd log any errors?

Is this a known behaviour ?

Or am I doing something the wrong way ?

Kernel version is 2.6.25

James Chapman
Katalix Systems Ltd
Catalysts for your Embedded Linux software development

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