KVM-ok -- Your CPU does not support KVM extensions

@alejo wrote:

I just installed VIRL and no CPU extensions, what is that?

A typical error that is missed during the installation or is noticed during the installation is that virtualization support is not enabled or not supported by the host CPU. This is really important when we are talking about any .ova deployment. VIRL is a VM and also a host. What this means is that the VM you deployed on your workstation or ESXi server will in turn deploy virtual machines within it self. This is called nested virtualization. For this to function properly we need to be able to pass the CPU "flags" from the host to the VIRL virtual machine. In essence tricking the VM to thinking it has direct access to the CPU.

Awesome. How do I check it?

The first command we ask you to run is this:

sudo kvm-ok

You already ran this command which is most likely why you are reading this.
But we need to know what is the model CPU you have and what flags are reported. For this we ask that you run these commands:

lscpu | egrep 'Arch|On-Line|Vend|Virt'
egrep -wo 'vmx|ept|svm|npt|ssse3' /proc/cpuinfo  | sort | uniq

If you are not sure your CPU model
cat /proc/cpuinfo |grep 'model\|MHz\|proc'

Those commands will give us an idea of what CPU you are using and if it will in fact support nested virtualization. In particular, we need the CPU to support VTx and EPT (Intel) and AMD-v and RVI (AMD) extensions.
If they fail to report the appropriate flags, check to make sure your CPU model supports those features. You can check your CPU model below:
intel
AMD

If your CPU does support the features then you need to make sure they are enabled in BIOS. Typically they can come disabled from the mfg. You may have to search a bit through your BIOS screens as the location differs. Sometimes you will find the features under "Security".

OK. my CPU supports nested virtualization. Still not working!

Due to some unexplained reason it is possible that the VT-x setting is not written to the configuration file of the VIRL VM. This can happen on VMWare Workstation or ESXi. No matter the fix is the same. You will need to open the .vmx file and ensure this line is present: vhv.enable = "TRUE" as described in this post.
If you had to modify the file you will need to shutdown the VM completely and then start it. Otherwise the setting will not take effect. It is not uncommon for the setting to revert so it is worthwhile to verify the setting took after the reboot.

This is getting old, still not working!

Now collect some logs (Described here) start a new thread and attach the zip file. Don't forget to include the output of all the commands listed in this post. We really do need that output.

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