查看操作系统是否支持kvm嵌套

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[root@compute03 images]# cat /sys/module/kvm_intel/parameters/nested
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How to enable Nested virtualization in OpenStack Cloud
I have installed OpenStack using PackStack in our physical server. After successfully installed, verified that the setup is working fine.
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/ H4 G: B* r( H7 cWe need to enable nested virtualization OpenStack cloud at the kernel level:
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8 B- J' n  x) w4 e2 I[root@openstack]#echo "options kvm-intel nested=y" >> /etc/modprobe.d/dist.conf
Modify the following settings in nova.conf file.
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virt_type=kvm
...
$ z+ y, `  B( u: Z  g! T- mcpu_mode=host-passthrough
“host-passthrough” – use the host CPU model exactly
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this causes libvirt to tell KVM to passthrough the host CPU with no modifications. The difference to host-model, instead of just matching feature flags, every last detail of the host CPU is matched.
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! T" v5 }! {& f. m( q" I! o: }- N! w) f“host-model” –  clone the host CPU feature flags

Reboot your compute Host
Validate that nested virtualization is enable at the kernel level:
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[root@openstack]# cat /sys/module/kvm_intel/parameters/nested
Y
( U0 @7 F! Y, M5 ~' j: q% eLaunch new instance on this node, and validate that your instance at the vmx cpu flag enable:

[root@nested ~]# cat /proc/cpuinfo | grep vmx
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon rep_good nopl eagerfpu pni pclmulqdq vmx ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm tpr_shadow vnmi flexpriority ept fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid xsaveopt
! A9 b' p. Y3 Cflags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon rep_good nopl eagerfpu pni pclmulqdq vmx ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm tpr_shadow vnmi flexpriority ept fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid xsaveopt
4 c- r- `' v! M( YThat’s all. A new virtual machine will be running as a hypervisor.