qemu命令总结¶

https://medium.com/@calerogers/gpu-virtualization-with-kvm-qemu-63ca98a6a172

kvmgt¶

PCI 透传¶

$ tail -f /var/log/syslog
$ tail -f /var/log/libvirt/qemu/${domain}.log

vim /etc/default/grub

add " intel_iommu=on vfio_iommu_type1.allow_unsafe_interrupts=1"¶

GRUB_CMDLINE_LINUX="quiet splash loglevel=2 intel_iommu=igfx_off i915.hvm_boot_foreground=1 i915.enable_cmd_parser=0 i915.enable_hangcheck=0 loglvl=all guest_loglvl=all conring_size=4M noreboot intel_iommu=on vfio_iommu_type1.allow_unsafe_interrupts=1"

OR

#add  " intel_iommu=on vfio_iommu_type1.allow_unsafe_interrupts=1"
$ vim /boot/grub/grub.cfg

$ tee hostdev.xml <<-"EOF"
<hostdev mode='subsystem' type='pci' managed='yes'>
  <driver name='vfio'/>
  <source>
        <address domain='0x0000' bus='0x00' slot='0x14' function='0x0'/>
  </source>
</hostdev>
EOF

$ sudo virsh nodedev-dettach pci_0000_00_14_0
$ sudo virsh nodedev-reattach pci_0000_00_14_0

$ virsh attach-device --config ${domain} ./hostdev.xml
$ virsh attach-device ${domain} ./hostdev.xml

$ virsh detach-device ${domain} ./hostdev.xml

virsh 与 qemu-img¶

常用命令¶

列出 CPU Models

$ cat /usr/share/libvirt/cpu_map.xml
$ virsh cpu-models x86_64

# virsh
#  https://wiki.libvirt.org/page/Failed_to_connect_to_the_hypervisor

virsh --connect qemu+ssh://username@remove.host.com/system list
virsh --connect qemu+ssh://root@192.168.8.204/system --all

# spice端口
netstat -ntpl | grep qemu
virsh domdisplay --type spice {Id or Name}

# 创建镜像
qemu-img create -f qcow2 ubuntu-14.04.qcow2 20G
qemu-img info ubuntu-14.04.qcow2

# 镜像压缩
qemu-img convert -p -c -O qcow2 source.img destination.qcow2

# resize
qemu-img resize source.qcow2 +10G

# 创建外部快照
qemu-img create -f qcow2 -b base.qcow2 snapshot.qcow2

# 内部快照
qemu-img snapshot -l    source.qcow2  # 查看
qemu-img snapshot -c s1 source.qcow2  # 创建
qemu-img snapshot -a s1 source.qcow2  # 还原

# Committing Changes
# https://dustymabe.com/2015/01/11/qemu-img-backing-files-a-poor-mans-snapshotrollback/
#
$ sudo qemu-img info /guests/F21server.qcow2.snap
image: /guests/F21server.qcow2.snap
file format: qcow2
virtual size: 20G (21474836480 bytes)
disk size: 15M
cluster_size: 65536
backing file: /guests/F21server.img

$ sudo qemu-img commit /guests/F21server.qcow2.snap
Image committed.

# 重改基础镜像
$ qemu-img rebase [-u] -b /PATH/TO/base.qcow2 linux.qcow2 # -u 指 unsafe 模式,需检验,常用于基础镜像移动位置或重命名之后.

How to create Snapshot of Guest machine in Libvirt

virsh snapshot-create-as --domain srv7 --name srv7-snapshot_1  # 创建快照
virsh snapshot-list srv7                                       #  列出
virsh snapshot-info srv7 srv7-snapshot_1                       #  info
virsh snapshot-revert srv7 srv7-snapshot_1                     #  还原
virsh snapshot-delete srv7 srv7-snapshot_1                     #  删除

串口¶

libvirt使用虚拟机的串口和控制台

磁盘¶

# ubuntu 14 安装libguestfs
$ sudo apt-get install libguestfs-tools

# centos 7 安装libguestfs
$ yum install libguestfs-winsupport  # ntfs
$ yum install libguestfs-tools       # virt-format

$ sudo qemu-img create -f qcow2 disk 20G
$ sudo virt-format --filesystem ntfs -a disk.qcow2

$ virt-ls -a  image.qcow2 /
$ virt-copy-in test.txt -a  image.qcow2 /

CD¶

<disk type='file' device='disk'>
  <driver name='qemu' type='qcow2' cache='unsafe'/>
  <source file='/data/disk/3601b740-5726-11e8-a561-5254007aa05f_D.qcow2'/>
  <target dev='vdb' bus='virtio'/>
</disk>
<disk type='file' device='cdrom'>
  <driver name='qemu' type='raw'/>
  <source file='/cdata/isos/Windows-7-Ultimate-SP1-x64-677408.iso'/>
  <target dev='hda' bus='ide'/>
  <readonly/>
</disk>
<disk type='file' device='cdrom'>
  <driver name='qemu' type='raw'/>
  <source file='/cdata/isos/virtio-win.iso'/>
  <target dev='hdb' bus='ide'/>
  <readonly/>
</disk>
<disk type='file' device='cdrom'>
  <driver name='qemu' type='raw'/>
  <source file='/cdata/isos/mcos-tools.iso'/>
  <target dev='hdc' bus='ide'/>
  <readonly/>
</disk>
<disk type='file' device='floppy'>
  <driver name='qemu' type='raw'/>
  <source file='/cdata/isos/virtio-win.vfd'/>
  <target dev='fda' bus='fdc'/>
  <readonly/>
</disk>

声卡¶

查询支持的声卡

[localhost ~] $ sudo /usr/libexec/qemu-kvm --soundhw ?
Valid sound card names (comma separated):
ac97        Intel 82801AA AC97 Audio
hda         Intel HD Audio
pcspk       PC speaker

-soundhw all will enable all of the above

2 增加声卡

[localhost ~] $ sudo /usr/libexec/qemu-kvm --soundhw all

Creating Guests with PXE

Red Hat Enterprise Linux 6 Virtualization Host Configuration and Guest Installation Guide