tftp issue when starting 3 VMs

Derick Swanepoel dswanepoel at
Wed May 11 08:53:27 CEST 2005

On 5/10/05, Frank Mehnert <fm3 at> wrote:
> On Tuesday 10 May 2005 12:18, Derick Swanepoel wrote:
> > On 5/10/05, Frank Mehnert <fm3 at> wrote:
> > > On Tuesday 10 May 2005 11:01, Derick Swanepoel wrote:
> > > > I'm trying to start three VMs from grub (one master and two slaves),
> > > > but the tftp provider fails to load the third kernel. This file is the
> > > > same as the second VM's kernel, which loads successfully.
> > >
> > > Hmm, no idea. Has your L4Linux a driver for your network card included
> > > (it should not). Please post the full log file.
> >
> > The kernel used for the master VM has a driver for my network card,
> > but the two slave kernels do not. Note that everything works fine if I
> > start one master and one slave, or two slaves, but not one master and
> > two slaves.
> >
> > However, sometimes it does work, but very infrequently.
> This is exactly what I mean. If your master L4Linux instance grabs
> the network card, the tftp task owns the network card no longer and
> therefore is not able to load something. Note that tftp and L4Linux
> access the same hardware device. This works as long as they do it
> sequentially.
> To overcome this problem, you could load the slave L4Linux instances
> with grub, pass them to the bmodfs server and then start them using
> the bmodfs server (see generic_fprov/examples/bmodfs).
> > I've attached the boot log (it's very long and somewhat hard to make
> > sense of because the messages of the master and slave kernel are
> > interleaved :( )
> Hmm. According that log it seems that the master L4Linux instance
> initialized the netword card just while loading the seconds slave
> instance, eth0 of Linux is up immediately after the tftp failed.
> The right solution for this is to use only _one_ driver for your
> network device and to share the driver between tftp and L4Linux.
> Both tftp and L4Linux should also support the oshkosh backend.
> Or you don't use tftp at all and load the binaries using bmodfs
> (maybe this is easier to setup).

Thanks, I used bmodfs and it works.

One last question: is there a way to ensure that the modules loaded
using bmodfs start in a certain order? At the moment my slave L4Linux
instances start before the master and "run" starts somewhere in


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