KVM 虛擬機 XML 配置文件詳解

咱們使用 KVM 建立虛擬機後，會在 /etc/libvirt/qemu/ 路徑下生成該虛擬機的 xml 配置文件，不少時候，咱們會以此 xml 配置爲模板，進行修改後來建立新的虛擬機，這樣，就須要咱們瞭解該配置文件中各個字段的意思，下面，就對該文件作一說明：

<!--
WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE
OVERWRITTEN AND LOST. Changes to this xml configuration should be made using:
  virsh edit node1
or other application using the libvirt API.
-->

<!--
如下兩項無關緊要，因此在此註釋。
-->

<!--
<seclabel>......</seclabel>                                                               驅動安全標籤，可刪除
<resource>......</resource>                                                               資源設置，可刪除
-->

<domain type='kvm'>
  <name>node1</name>                                                                      <!--虛擬機名稱-->
  <uuid>8908d03b-0329-4105-851f-c93fd091e9e9</uuid>                                       <!--個性化設置，也能夠自行修改，作虛擬機模板時能夠刪除-->
  <memory unit='KiB'>2097152</memory>                                                     <!--虛擬機能使用的最大內存，此處爲2G，即：2*1024*1024-->
  <currentMemory unit='KiB'>2097152</currentMemory>                                       <!--在虛擬機中用 free -m 命令能夠看見的內存大小，通常與上面的最大內存值設爲同樣-->
  <vcpu placement='static'>2</vcpu>                                                       <!--CPU的數量-->
  <os>                                                                                    <!--系統引導設備配置，無需手動修改-->
    <type arch='x86_64' machine='pc-i440fx-rhel7.0.0'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>                                                                              <!--高級電源管理，無需手動修改-->
    <acpi/>
    <apic/>
  </features>
  <cpu mode='custom' match='exact' check='partial'>                                       <!--CUP配置，cpu mode能夠寫成'host-passthrough',意思是使用真機的CPU-->
    <model fallback='allow'>Westmere</model>
  </cpu>
  <clock offset='utc'>                                                                    <!--時鐘設置，能夠設置爲localtime-->
    <timer name='rtc' tickpolicy='catchup'/>
    <timer name='pit' tickpolicy='delay'/>
    <timer name='hpet' present='no'/>
  </clock>
  <on_poweroff>destroy</on_poweroff>                                                      <!--虛擬機關機命令-->
  <on_reboot>restart</on_reboot>                                                          <!--虛擬機重啓命令-->
  <on_crash>destroy</on_crash>                                                            <!--虛擬機強制重啓命令-->
  <pm>                                                                                    <!--內存及硬盤休眠設置，可刪除-->
    <suspend-to-mem enabled='no'/>
    <suspend-to-disk enabled='no'/>
  </pm>
  <devices>                                                                               <!--系統仿真設備，主板驅動類-->
    <emulator>/usr/libexec/qemu-kvm</emulator>                                            <!--仿真設備使用哪一個程序來仿真，這裏使用qemu-kvm來仿真-->
    <disk type='file' device='disk'>                                                      <!--硬盤配置，須要手動修改，能夠經過複製本段來建立新的磁盤-->
      <driver name='qemu' type='qcow2'/>                                                  <!--磁盤驅動類型-->
      <source file='/var/lib/libvirt/images/node1.img'/>                                  <!--磁盤路徑設置-->
      <target dev='vda' bus='virtio'/>                                                    <!--磁盤盤符設置-->
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>         <!--總線地址，下同，可刪除-->
    </disk>
    <controller type='usb' index='0' model='ich9-ehci1'>                                  <!--USB相關配置，可刪除，下同-->
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x7'/>
    </controller>
    <controller type='usb' index='0' model='ich9-uhci1'>
      <master startport='0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0' multifunction='on'/>
    </controller>
    <controller type='usb' index='0' model='ich9-uhci2'>
      <master startport='2'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x1'/>
    </controller>
    <controller type='usb' index='0' model='ich9-uhci3'>
      <master startport='4'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x2'/>
    </controller>
    <controller type='pci' index='0' model='pci-root'/>                                    <!--PCI設備配置，可刪除-->
    <controller type='virtio-serial' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
    </controller>
    <interface type='network'>                                                             <!--網卡設置，可複製本段來添加新的網卡-->
      <mac address='52:54:00:74:1c:9e'/>                                                   <!--網卡MAC地址，可刪除-->
      <source network='default'/>                                                          <!--指定網卡鏈接的交換機-->
      <model type='virtio'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>          <!--總線地址，可刪除-->
    </interface>
    <serial type='pty'>                                                                    <!--串口終端，須要保留，下同-->
      <target type='isa-serial' port='0'>
        <model name='isa-serial'/>
      </target>
    </serial>
    <console type='pty'>
      <target type='serial' port='0'/>
    </console>
    <channel type='unix'>                                                                  <!--虛擬機通信控制接口-->
      <target type='virtio' name='org.qemu.guest_agent.0'/>
      <address type='virtio-serial' controller='0' bus='0' port='1'/>
    </channel>
    <channel type='spicevmc'>                                                              <!--圖形圖像相關配置，能夠刪除-->
      <target type='virtio' name='com.redhat.spice.0'/>
      <address type='virtio-serial' controller='0' bus='0' port='2'/>                      <!--串口設備，須要保留串口終端-->
    </channel>
    <input type='tablet' bus='usb'>                                                        <!--數位板，如筆記本電腦的觸摸板等，可刪除-->
      <address type='usb' bus='0' port='1'/>
    </input>
    <input type='mouse' bus='ps2'/>                                                        <!--鼠標-->
    <input type='keyboard' bus='ps2'/>                                                     <!--鍵盤-->
    <graphics type='spice' autoport='yes'>                                                 <!--圖形圖像顯卡相關配置，能夠刪除-->
      <listen type='address'/>
      <image compression='off'/>
    </graphics>
    <sound model='ich6'>                                                                   <!--聲卡相關設置，能夠刪除-->
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
    </sound>
    <video>                                                                                <!--圖形圖像顯卡相關配置，能夠刪除-->
      <model type='qxl' ram='65536' vram='65536' vgamem='16384' heads='1' primary='yes'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
    </video>
    <redirdev bus='usb' type='spicevmc'>                                                   <!--設備重定向，能夠刪除，下同-->
      <address type='usb' bus='0' port='2'/>
    </redirdev>
    <redirdev bus='usb' type='spicevmc'>
      <address type='usb' bus='0' port='3'/>
    </redirdev>
    <memballoon model='virtio'>                                                            <!--內存氣泡，能夠動態調整內存-->
      <address type='pci' domain='0x0000' bus='0x00' slot='0x08' function='0x0'/>
    </memballoon>
  </devices>
</domain>

這裏採用源文件註釋的方式對字段進行說明，能夠是更方便的瞭解字段意思，各位老鐵可直接複製粘貼，修改以後使用。