[lxc-devel] Last minute template addition - universal image based template

Wed Jan 15 03:07:44 UTC 2014

On Tue, Jan 14, 2014 at 10:02:39PM -0500, S.Çağlar Onur wrote:
> On Tue, Jan 14, 2014 at 9:50 PM, Stéphane Graber <stgraber at ubuntu.com> wrote:
> > 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.
> 
> Yep "[lxc-devel] [PATCH] lxc-download: Fix wrong option parsing"
> solved the issue :) I added
> 
>     echo 1 | sudo tee -a /sys/fs/cgroup/memory/memory.use_hierarchy > /dev/null
>     echo 1 | sudo tee -a /sys/fs/cgroup/cpuset/cgroup.clone_children > /dev/null
> 
>     for controller in /sys/fs/cgroup/*; do
>         sudo mkdir -p $controller/$USER
>         sudo chown -R $USER $controller/$USER
>         echo $$ > $controller/$USER/tasks
>     done
> 
> to the script and containers starting/stopping (I also updated gist).
> lxc-attach is now giving me trouble like this
> 
> [caglar at oOo:~] lxc-attach -n unpriv -P /home/caglar/lxcpath
> lxc-attach: Operation not permitted - failed to set namespace 'mnt'
> lxc-attach: failed to enter the namespace
> 
> Do you have any solution to that :)?

The only solution I have for you at this point is "use sudo"...

lxc-console should be working fine though. Chances are that ssh won't,
unless you're running a very very recent trusty guest (which includes my
PAM change that landed this morning in the archive).

It's unfortunate but attach doesn't work with unpriv containers at this
point. I remember mentioning this to Serge a while back but can't
remember whether we came to the conclusion that this was a kernel
limitation or because lxc-attach isn't attaching in the right way (which
may involve first calling idmap, then attach to the userns, then attach
to the other namespaces).

> 
> >>
> >> > 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
> >
> > _______________________________________________
> > 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
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