[Libguestfs] Fwd: Re: febootstrap in Debian

[Guido Günther]

Hi Richard,
On Tue, May 17, 2011 at 07:32:17PM +0100, Richard W.M. Jones wrote:
> [CC also to libguestfs mailing list]
> 
> On Tue, May 17, 2011 at 08:11:10PM +0200, Guido Günther wrote:
> > As to binary debs: I wonder if we can't just get away by adding the
> > needed packages as build-depends (so they end up installed on the buildd
> > before the package built) and modify febootstrap to look at the
> > _installed_ files instead of at the downloaded debs.
> > 
> > Looking at febootstrap_debian.ml this looks possible but very likely I'm
> > missing something. I'm not very good at OCaml though.
> 
> I guess the (non-obvious) thing you're missing is that we can't use
> installed configuration files, because the sysadmin may have changed
> them.  We need the original of all files, and we get those from the
> *.debs.
> 
> In the special case (and only in this special case) where we are
> building on the Debian builders, there's no sysadmin and so no one
> could have modified any configuration or other files.

Sure. I was only refering to the build servers here.

> However there may still be other problems I haven't seen.  How to get
> the list of files in each package (should be OK: dpkg -L).  How to
> resolve the dependencies so we know we have all packages / files?

dpkg -L should do the trick. For dependencies it seems you're using
"apt-cache depends --recurse -i %s" but I didn't look closely.

> With the Fedora builders, we have the *.rpm files left around and we
> use them.  Is that not the same in the Debian case?

I don't think we can assume we have all the debs around if we
build-depend on them. The packages might be already installed on the
system and therefore might be already removed from
/var/cache/apt/archives/. Could we build the appliance on the target
system and only update it on package upgrades?

> > Is the insmod.static issue somehow resolved? Maybe filing a wishlist bug
> > would help?
> 
> Still a bug AFAIK.
> 
> In Fedora we build module-init-tools from source and we don't do
> anything special[1] to get insmod.static, so I'm not sure why it
> doesn't exist on Debian too.

It just didn't get built and installed. I've filed a bug so we can at
least update febootstrap in Debian to 3.0. (Closes: #627353)

> > Having febootstrap/libguestfs in Debian would be great, I've met so many
> > people asking about it's status! Roland, do you plan to work on
> > libguestfs? If so I'd be happy to add you to the pkg-libvirt team.
> 
> Hope you can get something worked out.  Let me know if you need any
> more help.
> 
> libguestfs is legendarily hard to build ...

In fact I find it fun to build but unfortunately lack the time to work
on it.
Cheers,
 -- Guido

> 
> Rich.
> 
> [1] http://pkgs.fedoraproject.org/gitweb/?p=module-init-tools.git;a=blob;f=module-init-tools.spec;hb=HEAD
> 
> -- 
> Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
> virt-p2v converts physical machines to virtual machines.  Boot with a
> live CD or over the network (PXE) and turn machines into Xen guests.
> http://et.redhat.com/~rjones/virt-p2v
>