Re: [atomic-devel] Running docker-storage-setup from a UI

[Daniel J Walsh <dwalsh redhat com>]

On 04/12/2016 04:09 PM, Vivek Goyal wrote:
> On Tue, Apr 12, 2016 at 04:06:45PM -0400, Daniel J Walsh wrote:
> > On 04/12/2016 03:50 PM, Vivek Goyal wrote:
> > > On Tue, Apr 12, 2016 at 03:09:08PM +0300, Marius Vollmer wrote:
> > > > Hi,
> > > >
> > > > I am working on this:
> > > >
> > > >      https://github.com/cockpit-project/cockpit/wiki/Atomic:-Docker-Storage
> > > >
> > > > which is basically a UI inside Cockpit for docker-storage-setup.
> > > >
> > > > I am not super far along, but I am getting to the point where the UI
> > > > will need to actually run docker-storage-setup.
> > > >
> > > > - My basic idea is to write a new /etc/sysconfig/docker-storage-setup
> > > >    file and then run docker-storage-setup.  Is that the best approach for
> > > >    a UI?
> > > >
> > > > - Docker-storage-setup needs to run non-interactively, but I think it
> > > >    can't do that right now, and asks confirmation for various things.
> > > It already runs non-interactively. It is a service which runs on boot.
> > >
> > > >    Would it be acceptable to add a "--force-wipe" option to d-s-s, and
> > > >    maybe others?  I can do that at the same time as I write the code for
> > > >    the UI.
> > > So --force-wipe is a new functionality. What will it do?
> > >
> > > > - Just showing the contents of /etc/sysconfig/docker-storage-setup in
> > > >    the UI as the current state of things is not really correct, since
> > > >    docker-storage-setup might not have run since it was last changed, or
> > > >    it might have failed.
> > > >
> > > >    So I am thinking there could be something like
> > > >
> > > >      # docker-storage-setup status
> > > >      /dev/vda: ok, shared with OS
> > > >      /dev/sda: ok
> > > >      /dev/sdb: Not yet set up!
> > > >
> > > >      The Docker storage pool is not fully set up.  Run
> > > >      "docker-storage-setup" to complete the set up.
> > > I think first what would be nice is to display current docker
> > > configuration.
> > >
> > > What does "shared with OS" mean? Does it mean, it is in same volume
> > > group where rootfs is?
> > >
> > > >    This would output information about how things should be, and how they
> > > >    actually are.  (With an option for machine readable output.)  The
> > > >    above would be for VG="" and DEVS="/dev/sda /dev/sdb" where there was
> > > >    some sort of problem with /dev/sdb.
> > > >
> > > >    The machine readable output could maybe look like
> > > >
> > > >      # docker-storage-setup status -M
> > > >      /dev/vda:root
> > > What does "root" mean?
> > >
> > > >      /dev/sda:
> > > What does empty string after /dev/sda mean?
> > >
> > > Thanks
> > > Vivek
> > >
> > > >      /dev/sdb:error=missing
> > > >
> > > >    Or should we go full JSON right away?
> > > >
> > > > What do you think?  Am I heading down the wrong path?  If nobody stops
> > > > me, I'll hopefully make some PRs soon for this, and we can discuss the
> > > > details there.
> > Eventually adding a feature to do an `atomic migrate` to move from back end
> > to another would be nice
> >
> > With docker-1.10 you can do an
> >
> > atomic migrate export
> >
> > Change the back end
> >
> > atomic migrate import
> >
> > And switch from loopback devices to devmapper on physical storage or even
> > switch the backends altogether.
> >
> >  From devmapper to overlayfs to btrfs  and back again.
> IMHO, Thats sounds like out of scope for docker-storage-setup UI. That will be
> a better fit in UI designed for atomic.
>
> Thanks
> Vivek
Yes, I am just suggesting, that a fairly common pattern, might be to 
discover that you are running with bad settings, and you
want to change these settings, without necessarily having to touch the host.