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I have a Mac mini 2020 (with the Apple Silicon M1 chip).

I want it to boot up in verbose mode, i.e. the details of the boot process should be logged as text on the screen during bootup.

The following command is recommended by several articles:

sudo nvram boot-args="-v"

And this does indeed work fine on my Macbook Pro 2018 and Mac mini 2018, however, it seems to do nothing on my Mac mini 2020.

I have confirmed using nvram -p (and System Information) that the boot-args property is indeed set to -v, but it has no effect.

Is there some way to get this to work?

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In the past, verbose mode showed on the screen information that was logged by the kernel processes to traditional files. Also in the past, the logging system was overhauled to write these logs to a database first so they can be queried and some but not all of the logs end up in files.

Now, you can’t see the messages on screen and have to either know which files contain portions of the logged messages or query the database directly after the system has started (or indirectly if the system never completes startup).

Addressing the “what changed” with Apple Silicon is Apple completed the transition to all machines running under a T2 with a Secure Enclave and other architectural changes to the startup process. Some of these were present in Intel, but legacy behavior remained while Intel was executing the kernel code.

The old non-volatile ram commands don’t “work” on Apple Silicon.

Your diagnosis is correct - the store still sets values, but the system doesn’t take any action or read them at boot as far as I can tell.

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    I'm not trying to solve any particular problem. I'm just a developer and I like technical information to be shown instead of hidden, in case there is something interesting for me to see. – Klas Mellbourn Apr 10 at 20:08
  • This comment competes what I needed to augment my answer. 1. Use the console app or log show to browse past logs. 2. Use kernel debugging with a second Mac if you need to see the messages as they happen real time 3. Hardware changes and software changes have removed the verbose boot option @KlasMellbourn in a way you didn’t get a helpful error message when trying to set a variable. – bmike Apr 11 at 12:17
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    Wow, I knew nvram was gone but I had no idea there was no way to do a verbose boot. That seems like a very poor choice. Reading log files on a computer that can’t boot isn’t always straightforward. – Wowfunhappy Apr 11 at 16:17
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    You can still get all the information @Wowfunhappy log show is the new grep and log stream is the new tail the new system is an order of magnitude more powerful and capable than the old way. In practice recovery makes it so much easier to troubleshot a “failing boot” mac. – bmike Apr 11 at 17:44
  • @bmike I suppose the question is whether you can get to recovery. Perhaps if you can’t, the machine is too far gone to do much anyway... but I’m still skeptical. – Wowfunhappy Apr 11 at 18:53

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