Re: [Users] EL5 support for VirtIO SCSI?

Hello Stefan. Thanks. I understand qemu supports other scsi adapters however. See this <https://www.redhat.com/archives/libvir-list/2013-March/msg01254.html> post from earlier this year. That post makes reference to the following hbas: auto, buslogic, ibmvscsi. lsilogic, lsisas1068, lsisas1078, virtio-scsi, vmpvscsi. The post is referring to libvirt, so the number of adapters may be related to the various virtualization backends that libvirt can interface with. There are numerous references to qemu/qemu-kvm supporting other scsi adapters as well as AHCI SATA. I installed the Centos 6.4 based node, so perhaps the Fedora 19 based node has a newer qemu that supports more of these features? I might see if I can do an install of the Fedora 19 based node tomorrow. Ayal mentioned using 'hooks' to interface with qemu to possibly create a VM outside of the definitions that Ovirt allows. If I am understanding this correctly - how do I do this? Am I to expect some interface inconsistencies in the ovirt portal I I view a 'custom' VM like this?

So, in short - is there the potential for me to create a VM in ovirt that has a SCSI/SAS/SATA HBA and attach disk(s) to it (other than the virtio-scsi HBA which is not supported under EL5)? On Thursday, 14 November 2013 11:22 PM, Stefan Hajnoczi <stefanha(a)redhat.com&gt; wrote: On Thu, Nov 14, 2013 at 02:39:33AM -0500, Ayal Baron wrote: > > ----- 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. The only supported emulated SCSI HBA device is virtio-scsi. It was Tech Preview in RHEL 6.3 and became fully supported in RHEL 6.4. virtio-scsi is not available in RHEL 5. Stefan