Proposing a new infra design

[Ewoud Kohl van Wijngaarden]

On Mon, Jun 10, 2013 at 01:22:10AM -0400, Kiril Nesenko wrote:
> Ewoud Kohl van Wijngaarden wrote:
> > On Sun, Jun 09, 2013 at 08:03:32AM -0400, Kiril Nesenko wrote:
> > > Ewoud Kohl van Wijngaarden wrote:
> > > > On Sun, Jun 09, 2013 at 02:40:02AM -0400, Kiril Nesenko wrote:
> > > > > - Storage
> > > > > * For this design we need storage services that will be located in the
> > > > >   same DCs as our bare metal hosts.
> > > >
> > > > Could we use gluster where possible? At alterway for example. For
> > > > rackspace I'd prefer local storage per node, but I'll get to that later.
> > >
> > > gluster is a possible solution, but for gluster we still need external
> > > storage.
> >
> > You can run gluster on the hosts. Then you don't need external storage.
>
> For the gluster service we need more bare metal hosts right ? Or you want
> to run it on the existing hosts ?

I think you can run it on the existing hosts.

> > > > > * Storage for resources.ovirt.org - make no sense that VM stores RPMs
> > > > >   on it. Much better to use a VM with a small HD and use external
> > > > >   storage for storing RPMs.
> > > >
> > > > I don't quite understand this. I get that you'd want different
> > > > partitions, but why external storage? Whether the host manages this or
> > > > the guest, does it really make a difference?
> > >
> > > I am not sure on which servers resources.ovirt.org is running right
> > > now, but I would like to run our infra on our servers. For this
> > > purpose its better to create a VMs with a small HD and use ext.
> > > storage to save RPMs on it.
> >
> > Currently it's running on linode01. I still don't see the difference
> > between the hypervisor using the shared storage (nfs/iscsi/gluster/...)
> > and the VM. One advantage of the hypervisor doing it, is that you don't
> > have to worry about access to storage on the VM.
>
> What is linode01 ? bare metal ?

A virtual machine hosted at linode.

> What I meant is that VM should use ext. storage for storing the RPMs.
> In that case you will create a VM with a small HD and save some space
> on the DCs storage domain for another VMs.
>
> The second reason - if the VM will be corrupted somehow, we will have
> all our RPM repos on the ext. storage, so you will be able to install
> a new VM and mount this storage.

I don't really see the advantage. You can achieve the same by having
the hypervisor add a second disk. ovirt can also have floating disks so
you can detach it and attach it to a new VM. It's also not that much
space. A quick du -sh /var/www/html/releases tells me it's just 16G.