[Rdo-list] Puppet glusterers unite

[James Shubin]

On Wed, 2014-04-09 at 11:45 -0400, John Eckersberg wrote:
> James Shubin <jshubin at redhat.com> writes:
> > On Tue, 2014-04-08 at 17:42 -0400, John Eckersberg wrote:
> >> I'm working to configure libgfapi support on nova compute nodes.  In the
> >> old gluster module, there was a gluster::client class that just
> >> installed the required glusterfs-fuse package.  This class is used by
> >> astapor in a few places (compute/cinder/glance).  However there's no
> >> gluster::client class in the new module, so we'll need to remedy that
> >> somehow.
> > I think you've got the right idea in the next paragraph. I'll add some
> > more info...
> >
> >> 
> >> There is a class, gluster::mount::base, that ensures the packages are
> >> installed, and that class is used by each instance of gluster::mount.
> >> I'd like to reuse some of this, but I don't think we need all of it on
> >> the compute nodes (really we just need to install glusterfs-api).  The
> >> simple way would be to create a new class glusterfs::apiclient that just
> >> installs the package, and include that for the nova compute case.
> > Can you detail what functionality is missing and needed? Please make
> > sure to state if this is relevant to upstream (GlusterFS) or just
> > downstream (RHS/RHEL OSP, etc...) Is it just to install one package or
> > is there anything else?
> 
> Focusing just on this bit for now...
> 
> Libvirt supports using gluster as a storage backend.  It does this by
> calling libgfapi to interface with gluster directly.  There is no fuse
> layer or filesystem mounts needed.
> 
> If nova is configured with qemu_allowed_storage_backend=gluster, then it
> will generate the necessary libvirt xml to make this happen magically at
> launch time.  The only prerequisite is for libgfapi to be available on
> the compute nodes (and for libvirt to have been build with gluster
> support enabled).  The glusterfs-api package is what provides the
> required library.
Cool.

> 
> So, I just need a class to include which provides installation of the
> glusterfs-api package.  I was going to just add it as a normal package
> resource on my end, but I'm guessing this is something other folks might
> want to take advantage of, and the puppet-gluster module seems like the
> correct place to put it.  It's not particular to the downstream case;
> anyone who might want to use libgfapi as a client would want a canonical
> way to set it up.
Sounds like a good thing to add.

> 
> I'll submit a pull request with a new glusterfs::apiclient class that
> does nothing else but install the glusterfs-api package, and we can work
> from there.  Let me know if you'd prefer another name.  Maybe something
> like gluster::client::api, if you anticipate having other stuff under a
> gluster::client namespace?
Sounds good, except it's a bit tricky because of the versioning, so I
hacked it together for you:

https://github.com/purpleidea/puppet-gluster/tree/feat/libgfapi

To involve you more, I didn't even test it :) Please test and let me
know. If it meets your needs, I'll merge it into master.

HTH
James

> 
> John