Nested Virtualization

1. 先確定 Openstack 主機 nested kvm ENABLE。

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

2. nova.conf 的 virt_type=kvm 而且 cpu_mode=host-passthrough。

   [root@controller ~]# vim /etc/nova/nova.conf
   [root@controller ~]# egrep '^(virt|cpu)_' /etc/nova/nova.conf
   virt_type=kvm
   cpu_mode=host-passthrough
   

3. 重新啟動 openstack-nova 相關服務。

   [root@controller ~]# systemctl restart openstack-nova-*
   

4. instance crt2 先關機。

   [root@controller ~]# openstack server stop crt2
   

5. instance crt2 安裝時使用的 cpu mode 是 host-modle，將其修改為 host-passthrough。

   [root@controller ~]# vim /etc/libvirt/qemu/instance-00000017.xml 
   [root@controller ~]# grep 'cpu mode' /etc/libvirt/qemu/instance-00000017.xml 
     <cpu mode='host-passthrough' check='none'>
   

6. instance crt2 開機。

   [root@controller ~]# openstack server start crt2
   

7. 登入 instance crt2，查看 CPU 訊息，Virtualization: VT-x 表示支援虛擬化技術。

   [root@dywmac ~]# ssh -X 163.17.xx.xxx
   [root@deyu ~]# lscpu 
   Architecture:          x86_64
   CPU op-mode(s):        32-bit, 64-bit
   Byte Order:            Little Endian
   CPU(s):                4
   On-line CPU(s) list:   0-3
   Thread(s) per core:    1
   Core(s) per socket:    1
   Socket(s):             4
   NUMA node(s):          1
   Vendor ID:             GenuineIntel
   CPU family:            6
   Model:                 63
   Stepping:              2
   CPU MHz:               2299.996
   BogoMIPS:              4599.99
   Virtualization:        VT-x
   Hypervisor vendor:     KVM
   Virtualization type:   full
   L1d cache:             32K
   L1i cache:             32K
   L2 cache:              4096K
   L3 cache:              16384K
   NUMA node0 CPU(s):     0-3