virtio

When to enable RSS Recieve side scaling

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Since Virtio-Net Multi-Queue is not enabled by default in KVM like it is in VMware via Netqueue, what are the best benchmarks or performance collectors to use to determine if adding extra queues for RSS (receive side scaling) will be beneficial besides just looking at a hammered cpu? Answer AttributionSource : Link , Question Author … Read more

windows 7 as kvm guest installation with virtio drivers – detected virtio scsi disk shows wrong capacity

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I am trying to install windows 7 64bit as a kvm guest. I read here that I should install the virtio scsi driver during installation. I use virt-install to start my installation from the command line virt-install –connect qemu:///system \ –name win7vnc –ram 2048 –vcpus=2 –cpuset=auto \ –disk path=win7.img,bus=virtio –network=network=default,model=virtio,mac=RANDOM –graphics vnc,port=5900 –disk device=cdrom,path=../../isos/virtio-win-0.1-81.iso –disk … Read more

kvm/qemu host windows guest BSOD about driver_irql_not_less_or_equal for viostore.sys

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I have a KVM/Qemu host running 4 Windows Server 2012 guests and after upgrading the host from Ubuntu 12.04 to 14.04 I get blue screens with a bug check string of “driver_irql_not_less_or_equal” that is caused by driver “viostore.sys”. I don’t want to stay on 12.04 for ever. What can I do? Answer viostore.sys is the … Read more

How to switch in ws2012 from an IDE disk to a Virtio disk?

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I am running Windows server 2012 in a virtual machine under Debian Jessie. I tried to follow the Red Hat tutorial in order to switch on the Virtio drivers: 1) I downloaded from Debian the virtio drivers; the current version of the virtio-win.iso is 0.1.110. 2) I shutdowned the vm. 3) I added a new … Read more

Hardware raid, LVM and KVM cache policy

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I have a question about right cache policy for KVM using LVM and hardware raid-controller. So from the bottom: 1. We have LSI RAID controller 9260, 512Mb cache and BBU. Later we also will have CacheCade(SSD Drive as a cache) license and will use SSD. Now controller have virtual drives configured with “write back” and … Read more

KVM/libvirt: Using virtio disk driver in Debian installer

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I try to install Debian in a KVM-based VM using the virtio disk driver/bus and virt-install to run the installer. However, it seems that the installer lacks the virtio driver. Once I switch to bus=ide, the installation succeeds and afterwards, I can change back to virtio. Is there any way to let the installer recognize … Read more

RHEL 7.2 – cannot find attached vda disk during install via Mirantis Open Stack

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In trying to install RHEL 7 from an ISO (instead of deploying from an existing KVM image) in Mirantis Open Stack, I run into Anaconda not being able to find the attached disk – and so installation cannot proceed. There is a 160GB virtio disk (/dev/vda) attached to this image: But Anaconda cannot see it: … Read more

libvirt cannot boot windows-uefi guest with virtio storage

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i have hyper-v gen2 win-guest and need to migrate on kvm with libvirt. I convert one guest from vhdx to qcow2 with qemu-img, start it with qemu-system and hda-drive, install virtio drivers. After that i start it with virtio storage with that commandline: qemu-system-x86_64 -machine type=pc-q35-2.8 \ -accel kvm -cpu host \ –bios /usr/share/OVMF/OVMF_CODE.fd \ … Read more