Re: [Vserver] Multiple Routing Tables (Was: PPP inside VServer)

From: Eugene Roux <>
Date: Tue 05 Sep 2006 - 14:10:07 BST
Message-Id: <1157461807.4848.31.camel@norbert>

On Tue, 2006-09-05 at 07:37 -0500, Michael S. Zick wrote:
> On Tue September 5 2006 02:52, Eugene Roux wrote:
> >
> > Current Status:
> > * Multiple VEs are up and stable.
> > * VEs see their serial devices (all mapped to "/dev/modem").
> > * Connecting to "/dev/modem" using "cu -l" gives sane results.
> > * PPP connections establishes fine when tried individually.
> > * Trying to bring up more than one PPP interface at a time causes
> > the second to abort when it tries to set a default route.
> >
> > Any suggestions and/or tips?
> >
> man pppd
> See the: nodefaultroute and replacedefaultroute options.

Hmm... 'nodefaultroute', used in combination with a bit 'ip rule'
hackery might be the answer here.

Unfortunately it's been some years since I've done that: one forgets...
Time to stretch the mind again.

> They should give you control of the trying to set a default
> route.
> You might check how many /dev/ppp0 devices are trying to
> be set up also. ppp usually makes the connection:
> ppp? <-> /dev/something

This is correct, but fortunately :-

> Since routing is on the host, you might have to poke at
> the ppp code to get it to take an option for the device
> name. I.E: pppdev=ppp0 (vserver 0), pppdev=ppp1 (vserver 1)

This already happens. As far I can determine, the second Vserver is
allocated the 'ppp1' interface as an instance of '/dev/ppp'.

Where it all comes crashing down is when the second ppp interface then
tries to set a default route and the first will -- quite understandably
I think -- not give it up util it's done.

This is the reason I have to try and convince each Vserver that it has
it's own default route. Easy enough to do in Xen or VMWare since each
Server is a separate entity with bridged networking; not quite as simple
to accomplish in Linux-Vservers...

Mind you, Xen isn't at all easy to get going with multiple PPP dial-out
interfaces if you don't have a Vandepool/Pacifica enabled server, so
that point is really quite moot.

> It may be that you have to many ppp0 devices visible from
> the host (or you would if it wasn't aborting).

Fortunately not... Al least I sincerely hope not, otherwise I'd be in
deep trouble.


Eugéne Roux                "Fairy tales do not tell children the dragons
Cynical Romantic,                  exist.  Children already know dragons
Romantic Philosopher,              exist.  Fairy tales tell children the
Philosophising Cynic             dragons can be killed." G.K. Chesterton

Vserver mailing list

Received on Tue Sep 5 14:11:23 2006
[Next/Previous Months] [Main vserver Project Homepage] [Howto Subscribe/Unsubscribe] [Paul Sladen's vserver stuff]
Generated on Tue 05 Sep 2006 - 14:11:28 BST by hypermail 2.1.8