Unable to hold a key while powering on a Mac OS X VM?

[ant]

Hello.

I am trying to see what Mac's diagnostic/hardware test looks like in a Mac (OS X v10.10.5) VM with VMware Fusion v7.1.2, but I cannot seem to make it show up. What's wrong?

Thank you in advance.

[dariusd]

The Apple Hardware Test (or Apple Diagnostics) is a feature embedded in the firmware of Mac systems.  The virtual machine's firmware does not provide Apple Hardware Test/Diagnostics, so they are not available inside a virtual machine.

Is there a specific problem you are trying to diagnose, or were you just curious?

Cheers,

--

Darius

[Mikero]

Darius is, as pretty much always, correct.

You can set nvram boot-args however to force next boot to a particular mode (like target disk, single user mode, etc)

How to manage OS X boot options with wireless keyboards - CNET

[dariusd · Accepted solution]

Oh, I've made my fair share of blunders and bloopers in the past.

Another guide to using boot hotkeys in a VM is this one I put together a while ago: Using the Recovery Environment (Recovery HD) in an OS X Virtual Machine‌.  That document focuses on the recovery environment, but the same instructions are applicable for getting into single-user mode, safe mode, verbose mode, etc.  Editing the boot-args variable (as described in that CNET article) is handy if you expect to be using one of those modes often (particularly -v for verbose mode), but shouldn't be necessary for one-off usage unless you really can't manage click into the VM quickly enough.

And, by the way, we don't support Target Disk mode in a VM either.  :smileysilly:  (Nor do we support OS X Internet Recovery in a VM.)

Cheers,

--

Darius

[ant]

Weird. I didn't get any e-mail notifications of new post in my own forum thread.

Anyways, I was trying to hold down a bunch of keys for recovery, verbose, boot from USB drive, etc. It appears my timing was bad. However, I cannot boot from an USB flash drive with Option key when powering on? It is not supported? Why? I saw the text boot manager screen.

[dariusd]

On a physical Mac, the Option key will bring up the boot picker, which allows you to choose which drive to boot from.

We have not implemented such a pretty boot picker, so the Option key will get you to the EFI Boot Manager, which has much the same effect without being anywhere near as pretty.  (Have you seen what happens in Apple's boot picker if you eject/disconnect a boot device?  It vanishes in a puff of smoke!)

Somewhere on the EFI Boot Manager screen should be a USB device; Choosing that should allow your VM to boot from the USB drive.  Sometimes USB devices don't appear on the menu -- We have an open bug to address that problem.

There's actually a confluence of a few unfortunate and minor bugs/feature requests that makes it a bit more of a challenge than it should be to boot OS X from a USB drive in a VM.  The most obvious of these is that the Boot Manager does not recognize devices which are added to the VM once the Boot Manager is displayed.

If you can't get the USB drive to appear on the list, try this:

1. Power on your VM holding the Option key.

2. When the EFI Boot Manager screen appears, use the VM's toolbar to ensure that the USB drive is connected to the VM.

3. Choose "EFI Internal Shell".

4. In the wall of text which probably appears, look for any lines which say "Removable HardDisk".  Next to those, there will be a filesystem (fs) alias, something like "fs3".

5. At the shell prompt, type "fs3:" (or whatever the appropriate alias is) to change to that drive.

6. Now you have to find the bootloader.  Try just typing "boot.efi" and pressing Enter.  If that doesn't work, try "System\Library\CoreServices\boot.efi", or "EFI\BOOT\BOOTX64.EFI".

7. If all else fails, you can use the "dir" and "vol" commands to explore the filesystems and find the bootloader.

Nowhere near as pretty as Apple's boot picker, I know...  And there may well be easier ways.

Cheers,

--

Darius

[ant]

Darius: Ahh, that text boot manager was confusing. I was expecting a GUI. It sounds like VMware can't use Apple's GUI boot manager. I also saw the bootable USB flash drive finally. OK, I think I got my issues resolved. Thanks all!

[ant]

I think I figured out the problem. I can't reboot the machine to do the key trick. I have to power off the machine, and then do it. Is that right? Also, how can I connnect my USB devices before powering on? I can only do that when VM is powered on. Reboot won't let me press the boot key.

[dariusd]

You've pretty much found the whole the list of small bugs I mentioned above.

Try the steps I gave to use the EFI Shell to find and launch the OS from the USB drive.

Cheers,

--

Darius

[ant]

Dariusd: Yeah, I could not boot its bootloader since it terminated after 10 seconds back to console.

[dariusd]

Did it give an error message as it did so?  Usually if it bails out with a 10 second delay, it will print a message to explain why it's failed.  Launching it from the EFI Shell actually gives you the best chance to be able to see any bootloader messages.

If the bootloader won't launch from the EFI Shell, it is unlikely that booting it some other way will help.  (Not impossible, just unlikely.)

--

Darius

[ant]

http://i.imgur.com/oqgjIVT.png for a screen shot/capture (ignore my accidental 44 :smileysilly:). 😕

[dariusd]

Booting from the Recovery bootloader seems to be a bit more tricky than the regular bootloader (and sometimes a touch fragile too).

Here's a random thing to try based upon an earlier bug report, although I have no idea if it will actually work...  Instead of "cd"ing into com.apple.recovery.boot, try just typing these two commands at the Shell prompt:

   fs3:

   com.apple.recovery.boot\boot.efi

and see if it then boots.

Cheers,

--

Darius

[ant]

Darius: Woah, it worked!! Thanks. :smileygrin:

[ant]

Hello again.

Is it possible to boot from an USB Time Machine backup drive? http://i.imgur.com/FZp97Ky.pngfor a screen shot/capture inside VMware Fusion Pro v8.0.1 (yep, upgraded it too).

Thank you in advance.

[dariusd]

I've never tried.

What happens if you run "tmbootpicker.efi" at the EFI Shell prompt?

Cheers,

--

Darius

[ant]

Oops! I miscropped it. http://i.imgur.com/t3R3FTa.png for the corrected image.