Adding Stefan with the correct email this time.
----- Original Message ----- > Hi Paul, > > First of all, thanks for the detailed answer, it really helps. > See comments inline. > > ----- Original Message ----- > > Hello Itamar. > > The specific use case is a particular propriety filesystem that needs to > > see > > a scsi device. It will do scsi inquiry conmmands to verify suitability. > > In talking to the devs - of the filesystem - there is no way around it. I'd > > previously tried virtio-block - resulting in the /dev/vd* device - and the > > filesystem would not work. > > > > From doing a bit of web searching it appears the kvm/qemu supports (or did > > support) an emulated LSI scsi controller. My understanding is that the > > various virtualization platforms will emulate a well supported device (by > > the guest OSes) so that drivers are not an issue. For example this should > > allow a VM on Vmware vsphere/vcenter to be exported to Ovirt and have it > > boot up. The potential for further optimising the guest is there by > > installing ovirt/qemu/kvm guest utils that then allow the guest OS to > > understand the virtio nic and scsi devices. The guest could then be shut > > down, the nic and scsi controller changed and the guest booted up again. > > You can do the same thing in the Vmware world by installing their guest > > tools, shutting down the guest VM, then reconfiguring it with a vmxnet3 nic > > and pvscsi scsi adapter, then booting up again. > > It does seem somewhat inconsistent in Ovirt that we allow a choice of Intel > > e1000 or virtio nics, but do not offer any choice with the scsi adapter. > > virtio-scsi support was just recently added to oVirt to allow for scsi > passthrough and improved performance over virtio-blk. > I believe the emulated scsi device in qemu never matured enough but possibly > Stefan (cc'd) can correct me here. > For simplicity sake we kept choosing the controller type out but there is > nothing in the design preventing one from adding it. This is however the > first time I've actually heard any requests for it. > Note that using hooks you can still enable any functionality that qemu-kvm > supports but is not exposed in the GUI. It's not the most elegant way, but > it works. > > > Again, in Vmware land you can choose to have a scsi disk, but you choose > > which controller type it is attached to. In the current Ovirt 3.3.0 release > > you just chose a virtio-scsi disk, rather than there being a separation of > > the scsi disk and scsi controller. > > The messy situation with importing VMs from other platforms could be eased > > by > > allowing an emulated scsi controller as well as the preferred virtio > > controller. > > As mentioned previously, the support for this seems to be present in > > kvm/qemu. I wonder if there was a specific design decision (ie: some > > particular reason) to not support the approach I've just described? I can > > understand that in some cases simplicity is something to aim for though. > > I think this would make migration away from the dominant market leader - > > Vmware - easier and is something that would make ovirt/RHEV that more > > compelling. > > > > Getting back to my original query - 'open-vm-tools' support the vmware > > paravirtual scsi adapter and I am able to install these on EL5 and then see > > that adapter. It would be great if there was a similar initiative for the > > various virtio devices where you could install a packge/kmod and then allow > > some of the older OSes (of which there are still lots of VMs around for > > various reasons). There are obviously drivers for the various Windows > > flavours that take this approach. I'm surprised that for Linux it is just a > > case of 'if it's in the kernel you are running then it is supported'. > > > > I'm really pleased with the progress the ovirt has been making. I'm like to > > see it continue to knock down the various reasons out there as to why > > people > > with Vmware vcenter shops can't migrate over to it. > > > > Cheers, > > Paul > > > > > > On Wednesday, 13 November 2013 8:57 PM, Itamar Heim <[email protected]> > > wrote: > > On 11/13/2013 03:58 AM, Paul Jansen wrote: > > > Hi Rene. > > > I specifically need the scsi support (virtio-scsi). > > > I do know about the virtio-block support, which results in /dev/vd* > > > devices as you say. > > > From what I read even EL6 earlier than 6.3 does not support virtio-scsi > > > > > > Alternatively, does oVirt support an emulated scsi adapter of a > > > different type that would allow me to see scsi disks? > > > > may i ask why do you need the virtual disks to specifically be scsi? > > > > > > > > Regards, > > > Paul > > > > > > > > > On Wednesday, 13 November 2013 7:23 PM, René Koch (ovido) > > > < [email protected] > wrote: > > > On Wed, 2013-11-13 at 09:41 +0100, Sander Grendelman wrote: > > > > According to https://access.redhat.com/site/solutions/20511 > > > < https://access.redhat.com/site/solutions/20511 >virtio > > > > work on > rhel5.3. > > > > > > > > You have to edit /etc/modprobe.conf and generate a new initrd. > > > > > > > > > If you're installing the OS on a VirtIO disk this is done automatically > > > by anaconda. I just installed RHEL 5 on oVirt 3.3 with VirtIO disk and > > > everything worked out of the box. > > > > > > > > > > > > > > On Wed, Nov 13, 2013 at 9:32 AM, Sven Kieske < [email protected] > > > <mailto: [email protected] >> wrote: > > > > > Hi, > > > > > > > > > > afaik the rhel 5 kernel series just has not the necessary drivers for > > > > > all virtio stuff, so it's not supported and does not work, unless > > > > > you want to patch your own kernel. > > > > > > > > > > Am 13.11.2013 06:44, schrieb Paul Jansen: > > > > >> I have just set up an Ovirt 3.3.0 install and have done a test > > > install of Centos 6.4 in a VM. The VM was configured with an IDE drive > > > and a virtio-scsi drive. The Centos 6.4 install sees both drives OK. > > > > >> I'm wanting to do some testing on a product that is based on EL5, > > > but I'm finding that it cannot see the virtio-scsi drive. It does show > > > up in the output of 'lspci', but I don't see a corresponding 'sd' device. > > > > >> > > > > > > > > > There's no /dev/sd* device - the devices are named /dev/vd*... > > > > > > > > > > >> I've just tried installing Centos 5.10 and the support is not there. > > > > > > > > > Didn't test CentOS but RHEL 5 is working fine. > > > > > > > > > Regards, > > > René > > > > > > > > > > > > > >> > > > > >> Does anyone know of any tricks to allow EL5 to see the virtio-scsi > > > device? > > > > > > > > > > > > > > > -- > > > > > Mit freundlichen Grüßen / Regards > > > > > > > > > > Sven Kieske > > > > > > > > > > Systemadministrator > > > > > Mittwald CM Service GmbH & Co. KG > > > > > Königsberger Straße 6 > > > > > 32339 Espelkamp > > > > > T: +49-5772-293-100 > > > > > F: +49-5772-293-333 > > > > > https://www.mittwald.de < https://www.mittwald.de/ > > > > > > Geschäftsführer: Robert Meyer > > > > > St.Nr.: 331/5721/1033, USt-IdNr.: DE814773217, HRA 6640, AG Bad > > > Oeynhausen > > > > > Komplementärin: Robert Meyer Verwaltungs GmbH, HRB 13260, AG Bad > > > Oeynhausen > > > > > _______________________________________________ > > > > > Users mailing list > > > > > [email protected] <mailto: [email protected] > > > > > > http://lists.ovirt.org/mailman/listinfo/users > > > > _______________________________________________ > > > > Users mailing list > > > > [email protected] <mailto: [email protected] > > > > > > > http://lists.ovirt.org/mailman/listinfo/users > > > > > > > > > > > > > > > > > > _______________________________________________ > > > Users mailing list > > > [email protected] > > > http://lists.ovirt.org/mailman/listinfo/users > > > > > > > > > > > > > _______________________________________________ > > Users mailing list > > [email protected] > > http://lists.ovirt.org/mailman/listinfo/users > > > _______________________________________________ Users mailing list [email protected] http://lists.ovirt.org/mailman/listinfo/users
