OS X Guest no Safe Mode

[ChipMcK]

VirtualBox V4.3.2
Host OS X 10.9 Mavericks
any Guest OS X
refer to Startup key combinations for Intel-based Macs

Running a OS X Guest, I can not

1. get into Safe Mode
2. invoke Startup Manager (dual boot), or reasonable substitute.
3. get into Single User Mode
4. get into Verbose Mode
5. and so forth

I am restrict to booting from SATA Port 0, with no options.

Need the ability to, before the Guest boot/startup sequence, grant time to

1. give focus to OS X Guest window
2. press desired Command/Alt key combinations (listed in Startup key combinations for Intel-based Macs)
3. then have the startup/boot sequence invoked

A “DelayAtStartup” parameter would, perhaps, fill the bill. However, there is a need to specify a ’time period” value, specified by the user. For some users, five seconds is an eternity, while for others, twenty seconds is not be enough

Thank you in advance

[socratis]

any Guest OS X. refer to Startup key combinations for Intel-based Macs

The startup keys that you refer to are part of the Apple-custom-EFI. In order for VBox to "capture" those special Apple-specific-key-combinations, it would mean that the VBox developers would have to "mimic" the Apple-custom-EFI. It then wouldn't comply with the EFI specification which (IMHO) is more important than mirroring the Apple-custom-EFI setup.

[ChipMcK]

From Ticket #12468

Please consider to use

VBoxManage setextradata <vm> "VBoxInternal2/EfiBootArgs" <value>
to set boot-args variable.

Setting firmware NVRAM variables using "nvram" tool within guest in runtime is not supported.

As of May 1, 2014 this usage of VBoxInternal2 is not documented.
Is this OS X specific or is it generic to all *nix?

[rpmurray]

You mean this part on page 230 of the User Manual?

– By default, the VirtualBox EFI enables debug output of the Mac OS X kernel to help you diagnose boot problems. Note that there is a lot of output and not all errors are fatal (they would also show on your physical Mac). You can turn off these messages by issuing this command:

Code: Select all   Expand viewCollapse view

VBoxManage setextradata "VM name" "VBoxInternal2/EfiBootArgs" " "

To revert to the previous behavior, use:

Code: Select all   Expand viewCollapse view

VBoxManage setextradata "VM name" "VBoxInternal2/EfiBootArgs" ""

[ChipMcK]

If you should notice there is no mention of Safe Mode, etc.

And that lack makes such usage undocumented.

and under v4.3.10 it does not work

Code: Select all   Expand viewCollapse view

VBoxManage setextradata <vm> "VBoxInternal2/EfiBootArgs"  "-x"

[rpmurray]

You do realize that some boot arguments rely on Apple's EFI to function, and that VirtualBox is not implementing or emulating Apple's EFI but a more generic version of UEFI.

[ChipMcK]

You do realize that some boot arguments rely on Apple's EFI to function, and that VirtualBox is not implementing or emulating Apple's EFI but a more generic version of UEFI.

I read this as Linux distributions do not have a Safe Mode and therefore this is not an issue

[socratis]

You're not reading it correctly. The "Safe mode" option in Linux and the rest of the BIOS-booting OSes comes as a part of the OS itself, not something that is happening at the BIOS boot phase. The Cmd-S for OSX is happening at the EFI boot phase. My comment back in November, which rpmurray echoed as well, outlines the reason why you don't get to invoke those special modes in VBox's EFI implementation.

[ChipMcK]

You're not reading it correctly. The "Safe mode" option in Linux and the rest of the BIOS-booting OSes comes as a part of the OS itself, not something that is happening at the BIOS boot phase. The Cmd-S for OSX is happening at the EFI boot phase. My comment back in November, which rpmurray echoed as well, outlines the reason why you don't get to invoke those special modes in VBox's EFI implementation.

From Ticket #12468

Please consider to use

VBoxManage setextradata <vm> "VBoxInternal2/EfiBootArgs" <value>
to set boot-args variable.

Setting firmware NVRAM variables using "nvram" tool within guest in runtime is not supported.

As of May 1, 2014 this usage of VBoxInternal2 is not documented.
Is this OS X specific or is it generic to all *nix?

[VM2VM]

...outlines the reason why you don't get to invoke those special modes in VBox's EFI implementation.

I found this conversation quite interesting, since I'm wondering exactly how VBox implements EFI (or even UEFI for that matter.) Where in the sources can I look for this?

[socratis]

Not an expert, but, I would start looking at https://www.virtualbox.org/browser/vbox ... evices/EFI