[[proc_enabling-nested-virtualization-in-kvm]]
= Enabling nested virtualization in KVM

Nested virtualization allows you to run a virtual machine (VM) inside another VM while still using hardware acceleration from the host.

== Checking if nested virtualization is supported

For Intel processors, check the `/sys/module/kvm_intel/parameters/nested` file. For AMD processors, check the `/sys/module/kvm_amd/parameters/nested` file. If you see `1` or `Y`, nested virtualization is supported; if you see `0` or `N`, nested virtualization is not supported.

For example:

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cat /sys/module/kvm_intel/parameters/nested
Y
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== Enabling nested virtualization

To enable nested virtualization for Intel processors:

. Shut down all running VMs and unload the `kvm_probe` module:
+
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sudo modprobe -r kvm_intel
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. Activate the nesting feature:
+
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sudo modprobe kvm_intel nested=1
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+
. Nested virtualization is enabled until the host is rebooted. To enable it permanently, add the following line to the `/etc/modprobe.d/kvm.conf` file:
+
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options kvm_intel nested=1
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To enable nested virtualization for AMD processors:

. Shut down all running VMs and unload the `kvm_amd` module:
+
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sudo modprobe -r kvm_amd
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. Activate the nesting feature:
+
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sudo modprobe kvm_amd nested=1
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. Nested virtualization is enabled until the host is rebooted. To enable it permanently, add the following line to the `/etc/modprobe.d/kvm.conf` file:                        
+
----
options kvm_amd nested=1
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