virtualization--nested kvm

源网址：http://www.server-world.info/en/note?os=CentOS_6&p=kvm&f=13

Configure nested KVM. It's possible to install KVM and create virtual machines as nested KVM on KVM host.

KVM嵌套配置，可以在安装KVM后，在KVM主机中创建虚拟机实现KVM嵌套。

1、The Kernel of CentOS 6 is 2.6.32 and it does not support Nested KVM, so it's necessarry to update to supported Kernel for Nested KVM first.\

CentOS6是一个2.6.32版本的内核。它不支持KVM嵌套，因此在进行嵌套配置前，先硬升级内核到支持KVM嵌套版本。

[root@dlp ~]#yum -y install centos-release-xen

[root@dlp ~]#sed -i -e "s/enabled=1/enabled=0/g" /etc/yum.repos.d/CentOS-Xen.repo

[root@dlp ~]#yum --enablerepo=Xen4CentOS -y update kernel

[root@dlp ~]#vi /boot/grub/grub.conf

# add at the end of the line of kernel like follows

在kernel行最后添加如下内容：

kernel /vmlinuz-3.4.61-9.el6.centos.alt.x86_64 ro root=/dev/mapper/VolGroup-lv_root
rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD rd_LVM_LV=VolGroup/lv_swap SYSFONT=latarcyrheb-sun16
crashkernel=auto console=ttyS0,115200n8 rd_LVM_LV=VolGroup/lv_root
KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM

kvm-intel.nested=1

[root@dlp ~]#reboot

# confirm status ( it's OK if it is "Y" )

[root@dlp ~]#cat /sys/module/kvm_intel/parameters/nested
Y

2、Make sure the CPU model on your computer.

检查你的计算机CPU型号

[root@dlp ~]#virsh capabilities | egrep "/model|/vendor"
<model>SandyBridge</model>

# CPU Model

<vendor>Intel</vendor>

# CPU Vendor

<model>none</model>
<model>dac</model>

3、Edit the configuration of a virtual machine you'd like to nest like follows. It's OK to configure nested KVM and you can create virtual machines on the virtual machine nested.

如果你希望按如下方式嵌套就编辑虚拟机的配置文件，正确配置KVM嵌套后，你可以在虚拟机中嵌套创建一个虚拟机。
[root@dlp ~]#virsh edit www

# edit a virtual machine "www"

# add following lines

<cpu mode='custom' match='exact'> 

# CPU model

  <model fallback='allow'>SandyBridge</model> 

# CPU vendor

  <vendor>Intel</vendor>
  <feature policy='require' name='vmx'/>
</cpu>