[lxc-devel] Last minute template addition - universal image based template
Stéphane Graber
stgraber at ubuntu.com
Wed Jan 15 02:50:15 UTC 2014
On Tue, Jan 14, 2014 at 09:48:13PM -0500, Stéphane Graber wrote:
> On Tue, Jan 14, 2014 at 09:30:50PM -0500, S.Çağlar Onur wrote:
> > On Tue, Jan 14, 2014 at 9:24 PM, Stéphane Graber <stgraber at ubuntu.com> wrote:
> > > On Tue, Jan 14, 2014 at 09:12:31PM -0500, S.Çağlar Onur wrote:
> > >> Hey Stéphane,
> > >>
> > >> On Tue, Jan 14, 2014 at 6:52 PM, Stéphane Graber <stgraber at ubuntu.com> wrote:
> > >> > On Tue, Jan 14, 2014 at 06:38:43PM -0500, Dwight Engen wrote:
> > >> >> On Mon, 13 Jan 2014 20:56:23 -0500
> > >> >> Stéphane Graber <stgraber at ubuntu.com> wrote:
> > >> >>
> > >> >> [...]
> > >> >> >
> > >> >> > Yeah, I did a few last-minute changes.
> > >> >> >
> > >> >> > fstab is no longer required (only copied over if it's there).
> > >> >> >
> > >> >> > If the expiry file is messing, it's simply assumed that the container
> > >> >> > won't expire.
> > >> >>
> > >> >> Nice, that makes sense.
> > >> >>
> > >> >> [...]
> > >> >> > Now for Oracle, I guess it depends what's most useful for your users.
> > >> >> >
> > >> >> > Is there actually still a demand for 4.x? I thought at least RHEL 4.x
> > >> >> > went out of support last year.
> > >> >> >
> > >> >> > In any case, I suspect that starting with the latest of each supported
> > >> >> > release on i386 and amd64 is probably a good start.
> > >> >> > We can then expand that to include popular minor releases, possibly
> > >> >> > the last few 6.x?
> > >> >>
> > >> >> Yeah I think it makes sense to start with just x86_64 6.latest, and
> > >> >> we'll see how it goes from there.
> > >> >>
> > >> >> > > One question I have on this is that the rootfs (at least that the
> > >> >> > > Oracle template makes, not sure about others) isn't quite right
> > >> >> > > since the host name will have already been injected into config
> > >> >> > > files (for example /etc/hosts), but lxc-download wants to template
> > >> >> > > them itself. Should we add a switch to the distro template so it
> > >> >> > > knows when its being called to create a rootfs for lxc-download to
> > >> >> > > put LXC_NAME in there instead the --name it was passed?
> > >> >> >
> > >> >> > So currently my build script (Jenkins job) will call the template
> > >> >> > with:
> > >> >> > - --rootfs=/build-lxc/container/LXC_NAME/rootfs
> > >> >> > - --path=/build-lxc/container/LXC_NAME
> > >> >> > - --name=LXC_NAME
> > >> >>
> > >> >> Oh yeah, doh! Clever, that should make it work fine.
> > >> >>
> > >> >> [...]
> > >> >> > > I have not tried from a normal user account yet. Is it basically
> > >> >> > > that you expect the template to be run by a normal user, but be
> > >> >> > > running in a userns? Can you describe how mapped_uid is supposed to
> > >> >> > > be set? Thanks!
> > >> >> > -d oracle -r 6.5 -a x86_64 --server phocis/lxc-images --no-validate
> > >> >> > Yeah, lxc-create basically does all the magic we need there.
> > >> >> > When run as a user, it'll run the template in a userns mapped with the
> > >> >> > container's range.
> > >> >> >
> > >> >> > $mapped_uid appears to be set to the uid in the userns which maps back
> > >> >> > to the user's own uid outside of it and makes it possible to chown
> > >> >> > files back to the actual user.
> > >> >>
> > >> >> So I had to dig into the source to see how I could get this to work,
> > >> >> and tried passing a line like:
> > >> >>
> > >> >> lxc-create -P /home/dengen/ct -f /home/dengen/ct/dengen_id_map.conf -n ol65 -t download -- -d oracle -r 6.5 -a x86_64 --server lxchttp/lxc-images --no-validate
> > >> >>
> > >> >> where /home/dengen/ct/dengen_id_map.conf just has:
> > >> >> lxc.id_map = u 0 100000 10000
> > >> >> lxc.id_map = g 0 100000 10000
> > >> >>
> > >> >> in order to get mapped_uid in lxc-create to kick in. Sadly this didn't
> > >> >> work because lxc.spec is still installing lxc-create (and a lot more)
> > >> >> setuid, so the geteuid() check in create_run_template() isn't firing.
> > >> >> So my question is: which lxc binaries are supposed to be installed
> > >> >> setuid these days? Is it just lxc-user-nic? Once I know, I can go ahead
> > >> >> and fixup lxc.spec. Thanks.
> > >> >
> > >> > Oh, wow, I didn't realize some distros were still installing anything
> > >> > setuid these days, especially after we drop lxc-setuid and lxc-setcap
> > >> > from the upstream tree.
> > >> >
> > >> > So anyway, nowadays, the recommendation is for only lxc-user-nic to be
> > >> > setuid, everything else should always run as the user. When run as root,
> > >> > you'll end up with system containers, when run as a user, you'll get an
> > >> > unprivileged container.
> > >>
> > >> Should I expect [1] to work on saucy with trusty kernel? Here is what
> > >> I'm getting
> > >>
> > >> [caglar at oOo:~] ./unprivileged.sh
> > >> Creating unpriv with dir
> > >> Using image from local cache
> > >> Unpacking the rootfs
> > >> chown: invalid user: ‘-f’
> > >
> > > What shell is providing /bin/sh on your system?
> > >
> > > I confirmed that chown had a -f argument on both busybox, dash and bash,
> > > but apparently you're using something else.
> > >
> > > Anyway, I'll fix that particular failure by using a good old || true then.
> >
> > I'm using bash but I think problem is not the -f parameter but wrong
> > LXC_MAPPED_UID value.
>
> Well, turns out -f isn't in POSIX so I sent a patch anyway.
>
> >
> > Printing the LXC_MAPPED_UID via
> >
> > if [ -n "$LXC_MAPPED_UID" ] && [ "$LXC_MAPPED_UID" != "-1" ]; then
> > echo "***" $LXC_MAPPED_UID "***"
> > chown $LXC_MAPPED_UID -f $LXC_PATH/config $LXC_PATH/fstab || true
> > fi
>
> Now that's pretty odd... I just did a quick test here and I don't see
> where what you're seeing is coming from...
>
> stgraber at castiana:~/data/code/lxc/lxc$ lxc-create -t download -n p1 -- -d ubuntu -r trusty -a amd64
> called with: --path=/home/stgraber/.local/share/lxc/p1 --name=p1 --rootfs=/home/stgraber/.local/share/lxc/p1/rootfs -d ubuntu -r trusty -a amd64 --mapped-uid 65536
> Setting up the GPG keyring
> Downloading the image index
> Downloading the rootfs
> Downloading the metadata
> The image cache is now ready
> Unpacking the rootfs
>
> ---
> You just created an Ubuntu container (release=trusty, arch=amd64).
> The default username/password is: ubuntu / ubuntu
> To gain root privileges, please use sudo.
>
>
> stgraber at castiana:~/data/code/lxc/lxc$ sudo lxc-create -t download -n p1 -- -d ubuntu -r trusty -a amd64
> called with: --path=/var/lib/lxc/p1 --name=p1 --rootfs=/var/lib/lxc/p1/rootfs -d ubuntu -r trusty -a amd64
> Using image from local cache
> Unpacking the rootfs
>
> ---
> You just created an Ubuntu 14.04 LTS (amd64) container.
> The default username/password is: ubuntu / ubuntu
> To gain root privileges, please use sudo.
>
>
>
> Can you also patch your lxc-download to print "$*" and post the result here?
Nevermind that, I think I found the problem, patch sent.
>
> > shows this
> >
> > [caglar at oOo:~] ./unprivileged.sh
> > Creating unpriv with dir
> > Using image from local cache
> > Unpacking the rootfs
> > *** -- ***
> > chown: invalid user: ‘-f’
> >
> > ---
> > You just created an Ubuntu container (release=saucy, arch=amd64).
> > The default username/password is: ubuntu / ubuntu
> > To gain root privileges, please use sudo.
> >
> >
> >
> > >>
> > >> ---
> > >> You just created an Ubuntu container (release=saucy, arch=amd64).
> > >> The default username/password is: ubuntu / ubuntu
> > >> To gain root privileges, please use sudo.
> > >> Starting/Attaching/Stopping to unpriv
> > >> lxc-start: command get_cgroup failed to receive response
> > >> lxc-attach: failed to get the init pid
> > >> unpriv is not running
> > >> Destroying unpriv
> > >
> > > The rest of the failure is coming from you not having the proper
> > > cgroupfs setup. Try something like:
> > >
> > > for controller in /sys/fs/cgroup; do
> > > sudo mkdir -p $controller/$USER/lxc
> > > sudo chown -R $USER $controller/$USER
> > > echo $$ > $controller/$USER/lxc/tasks
> > > done
> > >
> > > This assumes that the top level clone_children and use_hierarchy are set
> > > to 1 prior to doing this.
> > >
> > > It's unfortunately a bit painful to setup by hand everytime but
> > > cgmanager should fix that once it lands.
> >
> > Ah right, will try with this.
> >
> > >>
> > >> [caglar at oOo:~] grep ERROR unpriv.log
> > >> lxc-start 1389751901.034 ERROR lxc_cgroup - Permission denied
> > >> - Could not create cgroup /unpriv
> > >> lxc-start 1389751901.034 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/hugetlb//lxc
> > >> lxc-start 1389751901.035 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/hugetlb/
> > >> lxc-start 1389751901.035 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/perf_event//lxc
> > >> lxc-start 1389751901.035 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/perf_event/
> > >> lxc-start 1389751901.035 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/blkio//lxc
> > >> lxc-start 1389751901.036 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/blkio/
> > >> lxc-start 1389751901.036 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/freezer//lxc
> > >> lxc-start 1389751901.036 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/freezer/
> > >> lxc-start 1389751901.036 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/devices//lxc
> > >> lxc-start 1389751901.036 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/devices/
> > >> lxc-start 1389751901.036 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/memory//lxc
> > >> lxc-start 1389751901.037 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/memory/
> > >> lxc-start 1389751901.037 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/cpuacct//lxc
> > >> lxc-start 1389751901.037 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/cpuacct/
> > >> lxc-start 1389751901.037 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/cpu//lxc
> > >> lxc-start 1389751901.037 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/cpu/
> > >> lxc-start 1389751901.038 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/cpuset//lxc
> > >> lxc-start 1389751901.038 ERROR lxc_cgroup - Permission denied
> > >> - cgroup_rmdir: failed to delete /sys/fs/cgroup/cpuset/
> > >> lxc-start 1389751901.038 ERROR lxc_start - failed to create
> > >> cgroups for 'unpriv'
> > >> lxc-start 1389751901.038 ERROR lxc_start - failed to spawn 'unpriv'
> > >> lxc-start 1389751901.039 ERROR lxc_commands - command
> > >> get_cgroup failed to receive response
> > >>
> > >> [1] https://gist.github.com/caglar10ur/8429502
> > >>
> > >> > --
> > >> > Stéphane Graber
> > >> > Ubuntu developer
> > >> > http://www.ubuntu.com
> > >> >
> > >> > _______________________________________________
> > >> > lxc-devel mailing list
> > >> > lxc-devel at lists.linuxcontainers.org
> > >> > http://lists.linuxcontainers.org/listinfo/lxc-devel
> > >> >
> > >>
> > >>
> > >>
> > >> --
> > >> S.Çağlar Onur <caglar at 10ur.org>
> > >> _______________________________________________
> > >> lxc-devel mailing list
> > >> lxc-devel at lists.linuxcontainers.org
> > >> http://lists.linuxcontainers.org/listinfo/lxc-devel
> > >
> > > --
> > > Stéphane Graber
> > > Ubuntu developer
> > > http://www.ubuntu.com
> > >
> > > _______________________________________________
> > > lxc-devel mailing list
> > > lxc-devel at lists.linuxcontainers.org
> > > http://lists.linuxcontainers.org/listinfo/lxc-devel
> > >
> >
> >
> >
> > --
> > S.Çağlar Onur <caglar at 10ur.org>
> > _______________________________________________
> > lxc-devel mailing list
> > lxc-devel at lists.linuxcontainers.org
> > http://lists.linuxcontainers.org/listinfo/lxc-devel
>
> --
> Stéphane Graber
> Ubuntu developer
> http://www.ubuntu.com
> _______________________________________________
> lxc-devel mailing list
> lxc-devel at lists.linuxcontainers.org
> http://lists.linuxcontainers.org/listinfo/lxc-devel
--
Stéphane Graber
Ubuntu developer
http://www.ubuntu.com
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