How To fix “This kernel requires an x86-64 CPU, but only detected an i686 CPU. This processor is unsupported in RHEL 7.” when booting from VirtualBox

Error: This kernel requires an x86-64 CPU, but only detected an i686 CPU.
This processor is unsupported in RHEL 7. 

centos-boot-error

[Note: This tutorial is under the assumption that your physical CPU is 64-bit and your installed host OS is 64-bit and will only work in these circumstances.]

Cause:

This mainly happens due two reasons:

  1. If you have a 64-bit OS installed but the VirtualBox OS type is accidentally changed/set to 32-bit after installation.
  2. If Vt-X (Virtualization) is disabled in the BIOS. (This can happen if you reset your BIOS to default settings which may have disabled Vt-X  bit).

Solution:

Step 1: Right Click on the Centos/RHEL OS which is giving you the error and then click on “Settings“.

virtualbox settings

Step 2: In General Tab, check the OS Type and see if you are able to change to “Redhat 64-bit” and follow step 4.

change os type

Step 3: If you are only able to see 32-bit entries in the OS type list and your physical CPU supports 64-bit, this means that Vt-X is disabled in your BIOS. So, restart your PC and boot into your BIOS, enable Vt-X.

For reference, I have a Asus Maximus VII Ranger Motherboard and here is how I enabled Vt-X in my BIOS.

enable vt-x

[Optional: If your CPU supports Vt-d, enable that too, it will improve functionality and performance of your Virtual Machine. Some CPUs will not have the Vt-d function, if you dont have it then you can ignore it]

optional step to enabled vt-d

Step 4: Restart your computer and boot back your CentOS/RHEL VM and it should come right up.

centos boot error fixed

Hope this fixed the issue. If this tutorial helped you,do  leave a thumbs up a comment below. Hope this helps! 🙂

If you have any sort of queries,  just leave a comment below and will get back to you. Don’t forget to follow my blog to get future updates! 😀

Regards,
ΞXΤЯ3МΞ

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