qemu-kvm创建参数分析

qemu的命令参数参考文档：

http://qemu.weilnetz.de/qemu-doc.html

下面是一个例子：

/usr/libexec/qemu-kvm -S -M rhel6.3.0 

-cpu Westmere,+rdtscp,+pdpe1gb,+dca,+pdcm,+xtpr,+tm2,+est,+smx,+vmx,+ds_cpl,+monitor,+dtes64,+pclmuldq,+pbe,+tm,+ht,+ss,+acpi,+ds,+vme 

-enable-kvm -m 2048

-smp 2,sockets=2,cores=1,threads=1 

-name inst-1219 -uuid 1cf7a47c-18ec-11e2-92db-14feb5dc2c72 -nodefconfig -nodefaults 

-chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/inst-1219.monitor,server,nowait 

-mon chardev=charmonitor,id=monitor,mode=control 

-rtc base=localtime -no-shutdown 

-device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2

-drive file=/dev/drVG/lv1567,if=none,id=drive-virtio-disk0,format=raw,cache=none,aio=native 

-device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x5,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 

-netdev tap,fd=22,id=hostnet0 

-device e1000,netdev=hostnet0,id=net0,mac=00:16:3e:66:90:9a,bus=pci.0,addr=0x3 

-netdev tap,fd=32,id=hostnet1 

-device e1000,netdev=hostnet1,id=net1,mac=00:16:3e:90:70:bd,bus=pci.0,addr=0x4 

-chardev pty,id=charserial0 

-device isa-serial,chardev=charserial0,id=serial0 

-device usb-tablet,id=input0 -vnc 0.0.0.0:9,password -vga cirrus 

-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x6

下面进行详细解释：

/usr/libexec/qemu-kvm -S -M rhel6.3.0 

-cpu Westmere,+rdtscp,+pdpe1gb,+dca,+pdcm,+xtpr,+tm2,+est,+smx,+vmx,+ds_cpl,+monitor,+dtes64,+pclmuldq,+pbe,+tm,+ht,+ss,+acpi,+ds,+vme 

-enable-kvm （允许KVM全虚拟化支持，该选项只有在LINUX编译时就加入了KVM支持的时候才有效）

-m 2048 （RAM内存为2048MB）

-smp 2,sockets=2,cores=1,threads=1 （模拟双核的SMP，最多指定两个sockets，每个socket1个core, 每个core1个thread）

-name inst-1219

-uuid 1cf7a47c-18ec-11e2-92db-14feb5dc2c72 （  system UUID ）

-nodefconfig （默认下qemu会从sysconfdir 和 datadir 读取配置， -nodefconfig禁止qemu读取   ）

-nodefaults  （默认qemu会创建serial port, parallel port, virtual console, monitor device, VGA adapter, floppy and CD-ROM drive and others， -nodefaults禁止创建这些默认的）

-chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/inst-1219.monitor,server,nowait （创建一个指定path的unix socket；server表示是一个linstening socket, nowait表示等待客户端连接的时候不应该阻塞）

-mon chardev=charmonitor,id=monitor,mode=control （把monitor重定向到宿主机设备/var/lib/libvirt/qemu/inst-1219）

-rtc base=localtime -no-shutdown 

-device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 （添加piix3-usb-uhci US B驱动支持）

-drive file=/dev/drVG/lv1567,if=none,id=drive-virtio-disk0,format=raw,cache=none,aio=native （添加一个盘，ID为driver-virtio-disk0, raw格式，无cache, 使用linux native aio）

-device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x5,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 （为driver-virtio-disk0的盘添加驱动virtio-blk-pci）

-netdev tap,fd=22,id=hostnet0 (connet host tap interface to vlan n，fd表示已打开的host tap interface的句柄 ,该虚拟网卡的ID为hostnet0)

-device e1000,netdev=hostnet0,id=net0,mac=00:16:3e:66:90:9a,bus=pci.0,addr=0x3 （为hostnet0网卡添加e1000设备驱动）

-netdev tap,fd=32,id=hostnet1 

-device e1000,netdev=hostnet1,id=net1,mac=00:16:3e:90:70:bd,bus=pci.0,addr=0x4 

-chardev pty,id=charserial0  （添加一个ID为charserial0的pty设备）

-device isa-serial,chardev=charserial0,id=serial0 （为charserial0设备 添加isa-serial设备驱动）

-device usb-tablet,id=input0

-vnc 0.0.0.0:9,password

-vga cirrus 

-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x6

最后用virsh dumpxml inst-1219

<domain type='kvm' id='99'>
  <name>inst-1219</name>
  <uuid>1cf7a47c-18ec-11e2-92db-14feb5dc2c72</uuid>
  <memory unit='KiB'>2097152</memory>
  <currentMemory unit='KiB'>2097152</currentMemory>
  <vcpu placement='static'>2</vcpu>
  <os>
    <type arch='x86_64' machine='rhel6.3.0'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <pae/>
  </features>
  <cpu mode='custom' match='exact'>
    <model fallback='allow'>Westmere</model>
    <vendor>Intel</vendor>
    <feature policy='require' name='tm2'/>
    <feature policy='require' name='est'/>
    <feature policy='require' name='vmx'/>
    <feature policy='require' name='ds'/>
    <feature policy='require' name='smx'/>
    <feature policy='require' name='ss'/>
    <feature policy='require' name='vme'/>
    <feature policy='require' name='dtes64'/>
    <feature policy='require' name='rdtscp'/>
    <feature policy='require' name='ht'/>
    <feature policy='require' name='dca'/>
    <feature policy='require' name='pbe'/>
    <feature policy='require' name='tm'/>
    <feature policy='require' name='pdcm'/>
    <feature policy='require' name='pdpe1gb'/>
    <feature policy='require' name='ds_cpl'/>
    <feature policy='require' name='pclmuldq'/>
    <feature policy='require' name='xtpr'/>
    <feature policy='require' name='acpi'/>
    <feature policy='require' name='monitor'/>
  </cpu>
  <clock offset='localtime'/>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <disk type='block' device='disk'>
      <driver name='qemu' type='raw' cache='none' io='native'/>
      <source dev='/dev/drVG/SNDACLOUD_lv1567'/>
      <target dev='vda' bus='virtio'/>
      <alias name='virtio-disk0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
    </disk>
    <controller type='usb' index='0'>
      <alias name='usb0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
    </controller>
    <interface type='bridge'>
      <mac address='00:16:3e:66:90:9a'/>
      <source bridge='br1'/>
      <target dev='vnet17'/>
      <model type='e1000'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>
    <interface type='bridge'>
      <mac address='00:16:3e:90:70:bd'/>
      <source bridge='br2.201'/>
      <target dev='vnet18'/>
      <model type='e1000'/>
      <alias name='net1'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
    </interface>
    <serial type='pty'>
      <source path='/dev/pts/25'/>
      <target port='0'/>
      <alias name='serial0'/>
    </serial>
    <console type='pty' tty='/dev/pts/25'>
      <source path='/dev/pts/25'/>
      <target type='serial' port='0'/>
      <alias name='serial0'/>
    </console>
    <input type='tablet' bus='usb'>
      <alias name='input0'/>
    </input>
    <input type='mouse' bus='ps2'/>
    <graphics type='vnc' port='5909' autoport='yes'/>
    <video>
      <model type='cirrus' vram='9216' heads='1'/>
      <alias name='video0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
    </video>
    <memballoon model='virtio'>
      <alias name='balloon0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
    </memballoon>
  </devices>
  <seclabel type='none'/>
</domain>

参考：

XML格式文档：

http://libvirt.org/format.html

qemu-kvm XML格式文档：

http://libvirt.org/drvqemu.html#xmlconfig

另外qemu参数和XML可以互转，参考：

http://libvirt.org/drvqemu.html

使用命令：

virsh domxml-from-native qemu-argv demo.args （根据参数生成XML）

 virsh domxml-to-native qemu-argv demo.xml （根据XML生成参数）

Example domain XML config

QEMU emulated guest on x86_64<domain type='qemu'>

  <name>QEmu-fedora-i686</name>
  <uuid>c7a5fdbd-cdaf-9455-926a-d65c16db1809</uuid>
  <memory>219200</memory>
  <currentMemory>219200</currentMemory>
  <vcpu>2</vcpu>
  <os>
    <type arch='i686' machine='pc'>hvm</type>
    <boot dev='cdrom'/>
  </os>
  <devices>
    <emulator>/usr/bin/qemu-system-x86_64</emulator>
    <disk type='file' device='cdrom'>
      <source file='/home/user/boot.iso'/>
      <target dev='hdc'/>
      <readonly/>
    </disk>
    <disk type='file' device='disk'>
      <source file='/home/user/fedora.img'/>
      <target dev='hda'/>
    </disk>
    <interface type='network'>
      <source network='default'/>
    </interface>
    <graphics type='vnc' port='-1'/>
  </devices>
</domain>

 

KVM hardware accelerated guest on i686

<domain type='kvm'>
  <name>demo2</name>
  <uuid>4dea24b3-1d52-d8f3-2516-782e98a23fa0</uuid>
  <memory>131072</memory>
  <vcpu>1</vcpu>
  <os>
    <type arch="i686">hvm</type>
  </os>
  <clock sync="localtime"/>
  <devices>
    <emulator>/usr/bin/qemu-kvm</emulator>
    <disk type='file' device='disk'>
      <source file='/var/lib/libvirt/images/demo2.img'/>
      <target dev='hda'/>
    </disk>
    <interface type='network'>
      <source network='default'/>
      <mac address='24:42:53:21:52:45'/>
    </interface>
    <graphics type='vnc' port='-1' keymap='de'/>
  </devices>
</domain>