virtualbox.org

I have installed VirutalBox Version 5.2.18 r124319 on a Redhat 7.5 Enterprise System (3.10.0-862.11.6.el7.x86_64). The CPU is Xeon X3480. In short, a 64 bit Linux on a 64 bit CPU.

Both VT-x and VT-d are enabled in BIOS. For VT-d I have played around with the additional options like "interrupt remapping", "Coherency", "ATS", and "Pass Through DMA", however, I'm not sure that I covered all possible combinations (and I don't believe that this is the problem (?) ).

With all these conditions VirtualBox does only show the 32 bit options for the possible guest systems to be installed. In my case I would like to set up a 64 bit Windows 10 guest, which does not seem to be possible.

In a next step I have removed all other virtualisation-related software, as I read, that this can take possession of the VT-x process, blocking it from VirtualBox. This did not help neither.

Can you please help? Did I forget something?

Create a 32bit guest VM. Power it on and wait for it to get to the "No bootable media found..." message. Power it off and then post the VBox.log file from that guest, it may give us a bit of a clue as to what is happening.

-Andy.

FAQ: I have a 64bit host, but can't install 64bit guests.

Dear Andy, dear mpack,

thanks a lot for your replies. I followed the instruction of Andy, please find the corresponding logfile attached. During set-up it says that my computer does not support VT-x technology. However I checked the processor description (see https://ark.intel.com/products/48501/In ... e-3_06-GHz), and it says that it supports VT-x and VT-d, and I have enabled both (I checked again in the BIOS).
I already knew the link provided by mpack. On viewtopic.php?f=1&t=62339 I followed the points 1 and 2. 3 more addresses Windows hosts, and I don't know how to ckeck this for the linux host. I have un-installed all other virtualisation software, which I could find, so maybe I addressed this point. Point 4 I cannot follow, as it does not give me the corresponding option.

Manuel

pou1 wrote:it says that it supports VT-x and VT-d, and I have enabled both (I checked again in the BIOS).

VBox.log wrote:

00:00:00.543156 HM: HMR3Init: Falling back to raw-mode: VT-x is disabled in the BIOS

The log file would seem to disagree with you! I would double and triple check that they are properly enabled in the BIOS. After that, you need to look at items like Secure Boot as they may get in the way, but I thought they gave different messages in the log file.

-Andy.

And if you enable/disable/toggle the VT-x setting, make sure that you shutdown the computer, as in "pull the plug", literally. For a minute or two...

Dear Andy and socratis,

thanks again for the hints. I triple checked and I pulled the plug for a coffee-break. Then I was disabling the VT-x and VT-d options, restarting, switching them back on, first just VT-x, then both VT-x and VT-d. Pulling the plug again. Restarting, ....

Nothing seems to help, it always gives the same feedback, that VT-x is not enabled, and yes, the log-file still disagrees with me.

Maybe I will try the "Secure Boot" route. Is this also in the BIOS?

Manuel

...
all right, in BIOS I had to disable "Trusted Execution Technology" or TXT. Now it shows me the 64 bit option.

Thanks again for your support

Manuel

Well done for finding the problem. Marking this as solved.