Kernel-Extensions Nvram – Resolve ‘general error’ when Setting boot-args on Sierra

kernel-extensionsnvram

I'm trying to temporarily disable KEX signing enforcement on my MBP since my company's VPN client (GlobalProtect) is failing the signature check now. This started yesterday when I did the OS upgrade to Sierra yesterday.

The solution should be running this command:

sudo nvram boot-args=kext-dev-mode=1

The problem is that I am getting the following response, and I can't figure out what it means or what to do about it (meaning I can't connect to my company network, too).

nvram: Error setting variable - 'boot-args': (iokit/common) general error

Does anybody have any ideas of things I could try or otherwise look at to track down the problem?

Thanks.

Best Answer

According to Apple KB : Prepare your institution for iOS 10 and macOS Sierra

...you must use the nvram command to properly set boot-args NVRAM variable. Starting with macOS Sierra, you must be booted to the recovery partition to run this command.

Related Solutions

Nvram boot-args to boot in target disk mode

From this (very useful!) page : http://www.cnet.com/news/how-to-manage-os-x-boot-options-with-wireless-keyboards/

I found the answer you want. And I quote:

The "boot-args" variable can be used for setting the above modes. but in addition if you need to load the system into Target Disk mode, you can do so by setting the "target-mode" PRAM variable in the following way (this will be enabled only once for the next time the system is started):
sudo nvram target-mode=1

It looks like you can't get it to do that on every boot - but you could write a startup script that waited for a minute then set that parameter again then rebooted. Note that without the delay, you would never be able to boot the machine again :)

Then if you ever did want to start the machine not in Target Disk Mode, you would simply kill the startup script while it was waiting for the minute.

MacOS – What does “sudo nvram boot-args=”debug=0x10“” do to the Mac

sudo nvram boot-args="debug=0x144"

This is a combination of kernel debugging features that will show you extra information about the kernel's processes, which can be exceptionally useful if a system is experiencing kernel panics. Another option is to use debug=0x14e, which will display even more logging options. The primary use for this is that it enables old-style kernel panics that show scrolled text on the screen about why the system panicked, instead of displaying the gray backdrop and the message to merely restart your system. Alternative debug options are the following, though these will likely only be useful to kernel programmers:

0x01 - Stop at boot time and wait for the debugger to attach

0x02 - Send kernel debugging output to the console

0x04 - Drop into debugger on a nonmaskable interrupt

0x08 - Send kernel debugging information to a serial port

0x10 - Make ddb the default debugger

0x20 - Output diagnostics information to the system log

0x40 - Allow the debugger to ARP and route

0x80 - Support old versions of gdb on newer systems

0x100 - Disable the graphical panic dialog screen

Source: Boot argument options in OS X

ddb is just a debugger. It's absolutely safe to enable those kinds of modes to collect information once you experienced system issues.

Best Answer

Related Solutions

Nvram boot-args to boot in target disk mode

MacOS – What does “sudo nvram boot-args=”debug=0x10“” do to the Mac

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