虚拟化技术KVM（9）虚拟机资源调整

将虚拟机的cpu、memory、disk进行调整, 模拟公有云中的服务器, 可以对cpu、内存以及磁盘进行调整, 依据于此来完成对虚拟机配置的调整;

#> cpu及memory的调整(须关机调整)
$ virsh edit VIRTUAL_MACHINES_NAME
<domain type='kvm'>
  <name>VIRTUAL_MACHINES_NAME</name>
  <uuid>752b7fc7-3446-40d3-9868-d46acf9a8b78</uuid>
  <memory unit='KiB'>16777216</memory>
  <currentMemory unit='KiB'>16777216</currentMemory>
  <vcpu placement='static'>4</vcpu>
  <os>
    <type arch='x86_64' machine='pc-i440fx-rhel7.0.0'>hvm</type>
    <boot dev='hd'/>
  </os>

#> disk磁盘增加
$ qemu-img create -f [raw/qcow2] /kvm/vdisks/VMACHINE_NAME_DATA_NUMBER.[raw/qcow2] size
$ virsh attach-disk VMACHINE_NAME /kvm/vdisks/VMACHINE_NAME_DATA_NUMBER.[raw/qcow2] vdx
$ virsh edit VMACHINE_NAME
......
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/ROOT/kvm/images/k8s-master-01.qcow2'/>
      <target dev='vda' bus='virtio'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
    </disk>
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw/qcow2'/>
      <source file='/kvm/vdisks/VMACHINE_NAME.raw/qcow2'/>
      <target dev='vdx' bus='virtio'/>
    </disk>
......
#> disk磁盘移除
$ virsh detach-disk VMACHINE_NAME vdx