[Lxc-users] * fix cached rootfs update * fix rootfs path * add handling of systemd (aka >f15)

[Ramez Hanna]

On Tue, Mar 6, 2012 at 5:11 PM, Serge Hallyn <serge.hallyn at canonical.com> wrote:
> Yes, I think ideally you'd have a single
>
> /var/lib/lxc/fedora-devs
>
> mounted from a single loopback or block device, with each container
> having a /var/lib/lxc/fedora-devs/<containername> directory, populated,
> for its dev, bind-mounted in through lxc.mount.entry.
>
> -serge
>
> Quoting rhanna at informatiq.org (rhanna at informatiq.org):
>> i can do that but i didn't do it brcause it could be done differently for different backingsrorage
>> I'll do it anyway and send patch later
>>
>> --
>> Sent from my Nokia N9On 6.3.2012 16:59 Serge Hallyn wrote:
>> Quoting Ramez Hanna (rhanna at informatiq.org):
>> > On Mon, Mar 5, 2012 at 10:28 PM,  <rhanna at informatiq.org> wrote:
>> > > From: InformatiQ <rhanna at informatiq.org>
>> > >
>> > >
>> > > Signed-off-by: InformatiQ <rhanna at informatiq.org>
>> > > ---
>> > >  templates/lxc-fedora.in |   35 +++++++++++++++++++++++++++--------
>> > >  1 files changed, 27 insertions(+), 8 deletions(-)
>> > >
>> > > diff --git a/templates/lxc-fedora.in b/templates/lxc-fedora.in
>> > > index e7f42a6..3f50895 100644
>> > > --- a/templates/lxc-fedora.in
>> > > +++ b/templates/lxc-fedora.in
>> > > @@ -69,11 +69,6 @@ EOF
>> > >  127.0.0.1 localhost $name
>> > >  EOF
>> > >
>> > > -    sed -i 's|.sbin.start_udev||' ${rootfs_path}/etc/rc.sysinit
>> > > -    sed -i 's|.sbin.start_udev||' ${rootfs_path}/etc/rc.d/rc.sysinit
>> > > -    chroot ${rootfs_path} chkconfig udev-post off
>> > > -    chroot ${rootfs_path} chkconfig network on
>> > > -
>> > >     dev_path="${rootfs_path}/dev"
>> > >     rm -rf $dev_path
>> > >     mkdir -p $dev_path
>> > > @@ -99,6 +94,23 @@ EOF
>> > >
>> > >     return 0
>> > >  }
>> > > +configure_fedora_init()
>> > > +{
>> > > +    sed -i 's|.sbin.start_udev||' ${rootfs_path}/etc/rc.sysinit
>> > > +    sed -i 's|.sbin.start_udev||' ${rootfs_path}/etc/rc.d/rc.sysinit
>> > > +    chroot ${rootfs_path} chkconfig udev-post off
>> > > +    chroot ${rootfs_path} chkconfig network on
>> > > +}
>> > > +
>> > > +configure_fedora_systemd()
>> > > +{
>> > > +    unlink ${rootfs_path}/etc/systemd/system/default.target
>> > > +    touch ${rootfs_path}/etc/fstab
>> > > +    chroot ${rootfs_path} ln -s /dev/null //etc/systemd/system/udev.service
>> > > +    chroot ${rootfs_path} ln -s /lib/systemd/system/multi-user.target /etc/systemd/system/default.target
>> > > +    #dependency on a device unit fails it specially that we disabled udev
>> > > +    sed -i 's/After=dev-%i.device/After=/' ${rootfs_path}/lib/systemd/system/getty\@.service
>> > > +}
>> > >
>> > >  download_fedora()
>> > >  {
>> > > @@ -170,7 +182,8 @@ copy_fedora()
>> > >
>> > >  update_fedora()
>> > >  {
>> > > -    chroot $cache/rootfs yum -y update
>> > > +    YUM="yum --installroot $cache/rootfs -y --nogpgcheck"
>> > > +    $YUM update
>> > >  }
>> > >
>> > >  install_fedora()
>> > > @@ -353,7 +366,7 @@ if [ "$(id -u)" != "0" ]; then
>> > >  fi
>> > >
>> > >
>> > > -rootfs_path=$path/$name/rootfs
>> > > +rootfs_path=$path/rootfs
>> > >  config_path=$default_path/$name
>> > >  cache=$cache_base/$release
>> > >
>> > > @@ -362,7 +375,7 @@ revert()
>> > >     echo "Interrupted, so cleaning up"
>> > >     lxc-destroy -n $name
>> > >     # maybe was interrupted before copy config
>> > > -    rm -rf $path/$name
>> > > +    rm -rf $path
>> > >     rm -rf $default_path/$name
>> > >     echo "exiting..."
>> > >     exit 1
>> > > @@ -388,6 +401,12 @@ if [ $? -ne 0 ]; then
>> > >     exit 1
>> > >  fi
>> > >
>> > > +type /bin/systemd >/dev/null 2>&1
>> > > +if [ $? -ne 0 ]; then
>> > > +    configure_fedora_init
>> > > +else
>> > > +    configure_fedora_systemd
>> > > +fi
>> > >
>> > >  if [ ! -z $clean ]; then
>> > >     clean || exit 1
>> > > --
>> > > 1.7.7.6
>> > >
>> >
>> > there is only problem about systemd not addressed by this script
>> > is that it does mount /dev which stops getty from starting on tty1
>> > so either make it start on any tty higher than what your host is using
>> > and allow that in your lxc cgroup conf
>> > or mount the $rootfs/dev to a different block dev that way systemd
>> > won't mount /dev
>>
>> Could the template create a 1M loopback file,
>> /var/lib/lxc/<container>/dev.loopback, populated with /dev and
>> mounted by a lxc.mount.entry?
>>
>> -serge
>>

creating a loopback file for each container will not work from
lxc.conf as lxc won't mount it, it has to be bound to a loopdevice
first
i was hoping to make it happen with no pre steps

any ideas? to avoid manual intervention at all

-- 
BR
RH
http://informatiq.org