[Libguestfs] supermin appliances and host connectivity

[Richard W.M. Jones]

On Thu, Jun 09, 2011 at 08:26:38PM +0200, Joel Uckelman wrote:
> On Wed, Jun 1, 2011 at 6:45 PM, Richard W.M. Jones <rjones at redhat.com>wrote:
> 
> > On Wed, Jun 01, 2011 at 03:10:20PM +0200, Joel Uckelman wrote:
> > > I think I've fished out the command-line options you send to qemu-kvm:
> > >
> > > qemu-kvm -kernel kernel -initrd initrd -hda root -device virtio-serial
> > > -serial stdio -chardev
> > >
> > socket,path=/home/uckelman/projects/lightbox/supermin/foo,id=channel0,name=org.libguestfs.channel.0
> > >
> > > Thanks for that.
> > >
> > > I can definitely run my appliance this way if I already have something
> > > listening on that FIFO before launching qemu. (E.g.: socat
> > > UNIX-LISTEN:foo STDOUT) The piece of the puzzle I'm still missing is
> > > how to connect to the socket from the guest side. I was expecting to
> > > find something in the guest's /dev, but I have the same entries there
> > > as before.
> >
> > It seems likely that you either don't have udev running in the guest
> > or your guest kernel is too old.  IIRC it has to be >= 2.6.36 in order
> > to support virtio-serial.
> >
> > Rich.
> >
> 
> Yes, I don't have udev running. Adding udev to the package list for building
> the appliance seems not to be enough, as there's apparently nothing starting
> it. What's the proper way to start udev in this situation?

Have a look at how libguestfs does it:

http://git.annexia.org/?p=libguestfs.git;a=blob;f=appliance/init;hb=HEAD

The rest of the code in the appliance/ subdirectory is useful
to look at too.

Rich.

-- 
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