[Engine-devel] Empty cdrom drive.

[Miki Kenneth]

----- Original Message -----
> From: "Ayal Baron" <abaron at redhat.com>
> To: "Yaniv Kaul" <ykaul at redhat.com>
> Cc: engine-devel at ovirt.org
> Sent: Wednesday, February 15, 2012 11:23:54 AM
> Subject: Re: [Engine-devel] Empty cdrom drive.
> 
> 
> 
> ----- Original Message -----
> > On 02/15/2012 09:44 AM, Igor Lvovsky wrote:
> > >    Hi,
> > > I want to discuss $subject on the email just to be sure that we
> > > all
> > > on the
> > > same page.
> > >
> > > So, today in 3.0 vdsm has two ways to create VM with cdrom :
> > >   1. If RHEV-M ask to create VM with cdrom, vdsm just create it
> > >   2. RHEV-M doesn't ask to create VM with cdrom, vdsm still
> > >   creates
> > >   VM with
> > >      empty cdrom. Vdsm creates this device as 'hdc' (IDE device,
> > >      index 2),
> > >      because of libvirt restrictions.
> > >      In this case RHEV-M will be able to "insert" cdrom on the
> > >      fly
> > >      with
> > >      changeCD request.
> > >
> > > In the new style API we want to get rid from stupid scenario #2,
> > > because
> > > we want to be able to create VM without cdrom at all.
> > > It means, that now we need to change a little our scenarios:
> > >   1. If RHEV-M ask to create VM with cdrom, vdsm just create it
> > >   2. RHEV-M doesn't want to create VM with cdrom, but it want to
> > >   be
> > >   able to
> > >      "insert" cdrom on the fly after this. Here we have two
> > >      options:
> > >      a. RHEV-M should to pass empty cdrom device on VM creation
> > >      and
> > >      use
> > >         regular changeCD after that
> > >      b. RHEV-M can create VM without cdrom and add cdrom later
> > >      through
> > >         hotplugDisk command.
> > >
> > > Note: The new libvirt remove previous restriction on cdrom
> > > devices.
> > > Now
> > >        cdrom can be created as IDE or VIRTIO device in any index.
> > >        It means we can easily hotplug it.
> > 
> > I didn't know a CDROM can be a virtio device, but in any way it
> > requires
> > driver (which may not exist on Windows).
> > I didn't know an IDE CDROM can be hot-plugged (only USB-based?),
> 
> It can't be hotplugged.
> usb based is not ide (the ide device is the usb port, the cdrom is a
> usb device afaik).
> 
> The point of this email is that since we want to support being able
> to start VMs *without* a cdrom then the default behaviour of
> attaching a cdrom device needs to be implemented in engine or we
> shall have a regression.
This is a regression that we can not live with...
> In the new API (for stable device addresses) vdsm doesn't
> automatically attach a cdrom.
> 
> > perhaps
> > I'm wrong here.
> > Y.
> > 
> > >
> > >
> > > Regards,
> > >      Igor Lvovsky
> > >
> > >
> > > _______________________________________________
> > > Engine-devel mailing list
> > > Engine-devel at ovirt.org
> > > http://lists.ovirt.org/mailman/listinfo/engine-devel
> > 
> > _______________________________________________
> > Engine-devel mailing list
> > Engine-devel at ovirt.org
> > http://lists.ovirt.org/mailman/listinfo/engine-devel
> > 
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