[HN Gopher] External boot disks still don't work properly with M...
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       External boot disks still don't work properly with M1 Macs
        
       Author : zdw
       Score  : 181 points
       Date   : 2021-02-10 15:40 UTC (2 days ago)
        
 (HTM) web link (eclecticlight.co)
 (TXT) w3m dump (eclecticlight.co)
        
       | evgen wrote:
       | Some options/ides from the team that does the SuperDuper backup
       | and disk dupe tool:
       | https://www.shirtpocket.com/blog/index.php/shadedgrey/thats_...
        
       | louwrentius wrote:
       | Even on an Intel Mini, USB-C boot takes much longer than internal
       | boot, seemingly due to Apple shenanigans.
       | 
       | I have worked with External SSDs on Macs for years. Partially
       | because to circumvent the Apple Price Tax.
       | 
       | But also to just treat storage as something easy to swap.
        
       | cletus wrote:
       | I don't use an external boot disk but I certainly understand why
       | people do. And yeah this needs to be fixed.
       | 
       | But is anyone else shocked at how well the transition to ARM has
       | gone for Apple? Because I am. I figured this would be something I
       | would avoid as long as possible but honestly I'd probably be
       | happy with this year's MBP M1 refresh.
        
         | whatthesmack wrote:
         | > But is anyone else shocked at how well the transition to ARM
         | has gone for Apple?
         | 
         | I totally get why some folks would want to wait for the next-
         | gen of these initial machines, but I'm not surprised at how
         | well it's gone.
         | 
         | I chose to buy the initial M1 MacBook Air model right-off-the-
         | bat. The reason for this is that I went through the last two
         | Mac CPU arch transitions (68k -> PPC, PPC -> x86), and the way
         | Apple was able to handle those was truly impressive to me. Plus
         | I really needed more built-in storage ASAP :)
        
       | marcodiego wrote:
       | I think we're just a few steps away from having our own devices
       | in such a deeply locked state that boot disks will eventually
       | stop working on any sufficiently modern system.
        
         | marcan_42 wrote:
         | Apple expended a significant amount of resources designing this
         | bespoke boot chain so that it _isn 't_ locked down and does in
         | fact let users run completely unsigned operating systems (as
         | long as they have physical access and give consent with their
         | local user credentials). In fact, the design goes further,
         | allowing individual installed OSes to have different security
         | levels, thus allowing users to get the benefits of _both_ a
         | completely opened up OS install and a fully Apple-vetted,
         | secureboot install.
         | 
         | They aren't going to backtrack on all that. That'd be silly.
         | 
         | So please stop the FUD about Apple locking their devices down;
         | this is a Mac, not an iPhone :-)
        
         | my123 wrote:
         | It's just a set of bugs here, because of it using a redesigned
         | boot chain. The bugs will be fixed, just takes some time.
         | 
         | Has nothing to do with trying to impose additional
         | restrictions.
        
           | marcodiego wrote:
           | > Has nothing to do with trying to impose additional
           | restrictions.
           | 
           | For now, maybe. Consider the time when microsoft was
           | partially successful to boot-lock arm devices: https://www.so
           | ftwarefreedom.org/blog/2012/jan/12/microsoft-c...
           | 
           | The old adage "do not assign to malice what can be properly
           | explained by stupidity" should not be blindly applied when it
           | involves powerful companies.
        
             | machello13 wrote:
             | IMO this line of thinking implies a lack of contextual
             | understanding about Apple's culture, strategy, and history.
             | Of course we can never predict 100% what big companies will
             | do, but we can be pretty sure Apple isn't interested in
             | doing that.
        
             | my123 wrote:
             | I can assure you here that it works on some drives but not
             | others because the boot chain on Apple Silicon Macs is
             | written from scratch, not using UEFI.
             | 
             | Bugs are being worked out slowly, and there's no reason to
             | assume bad intentions here. (I have an Apple M1 MacBook
             | Air, and it boots from a Samsung T7 external SSD just fine)
        
         | bitcharmer wrote:
         | No, it's just Apple. The rest of the world doesn't do this
         | nonsense.
        
           | coldtea wrote:
           | The rest of the world doesn't care about security?
        
           | ant6n wrote:
           | I can boot all other arm devices with usb? Huh, maybe I'll
           | get an android phone and chromebook after all.
        
             | bitcharmer wrote:
             | Is there something in ARM that prevents booting from
             | external disks? What about Raspberry Pi?
        
               | ant6n wrote:
               | Nah. Just that most manufacturers sell the devices in
               | such a deeply locked state that boot disks are not
               | supported.
               | 
               | Though ARM appears to be missing an open-spec BIOS/Boot
               | standard like x86 has.
        
               | floatboth wrote:
               | SBSA-compliant systems boot with UEFI+ACPI. Server
               | customers care about standardization, so boot was made
               | "boring" and basically identical to x86.
               | 
               | It's just the embedded junk (which includes Apple) that
               | doesn't care. Apple has vertical integration, they only
               | care about the full experience including their own OS.
               | Embedded SoC vendors only care about having some "BSP"
               | fork of Linux because that is enough to make a crappy
               | device with it. There's just, unfortunately, zero
               | motivation for these vendors to embrace standards.
        
         | breakingcups wrote:
         | Through stupidity _and_ malice.
        
       | michelb wrote:
       | This may be fine for the current M1 macs, since they are most
       | likely not used by professionals or people that will do
       | potentially installation damaging things, so a trip to the Apple
       | Store will suffice. But this better work once the pro machines
       | come out. It's already hard to recover data from the newer mac's
       | when your system installation has issues, not being able to boot
       | from another drive is going to suck.
        
         | rowanG077 wrote:
         | The pro machines are allready out. You can buy a Macbook pro M1
         | right now.
        
           | coldtea wrote:
           | Parent doesn't mean machines with "Pro" in their branding
           | name, they mean the models actually used by technical/cpu-
           | demanding pros in video/graphic design/audio/3d/etc. (non
           | technical/cpu-demanding professionals, e.g. some office
           | working just needing web and excel, can use Macbook Air or
           | whatever too).
           | 
           | And those aren't out yet, those would be the 16 MBP, the Mac
           | Pro, the iMac and iMac Pro, and so on.
        
             | Toutouxc wrote:
             | You can also use the "MacBook Air or whatever" to compile
             | code just as fast [1] as the 16" MBP.
             | 
             | If that isn't a cpu-demanding task then I don't know what
             | is.
             | 
             | (not trying to be rude, just that the Air is currently a
             | very capable and pro-tier machine)
             | 
             | [1] https://www.macrumors.com/2020/11/17/apple-
             | silicon-m1-compil...
        
               | sudosysgen wrote:
               | Those kinds of professionals won't be comparing it to
               | other MacBooks, but to other computers of the same form
               | factor. The M1 Macs still aren't the leader in multicore
               | performance or multicore performance per watt.
               | 
               | If you're a programmer that mostly relies on multicore
               | performance, the current M1 Macs aren't the gold
               | standard. Unless of course you are drawn to the OS or
               | something else.
        
               | coldtea wrote:
               | > _Those kinds of professionals won 't be comparing it to
               | other MacBooks, but to other computers of the same form
               | factor._
               | 
               | Not really, since most of those kinds of professionals
               | concerned already used Intel Macbooks. It's not like
               | they're gonna win the "build some tower yourself crowd".
        
               | sudosysgen wrote:
               | The new AMD Ryzen 5000 series laptops are faster
               | multicore than the M1 MacBooks. I'm not comparing towers,
               | a powerful desktop computer would absolutely murder an M1
               | MacBook in multicore, it wouldn't even be close.
        
               | rowanG077 wrote:
               | Can you send me a link of a ryzen 5000 laptop with the
               | same form factor? All of them I know are either >14
               | inches or are much thicker.
        
               | sudosysgen wrote:
               | Sure, if you're looking for the form-factor of a MacBook
               | Air, there are quite a few. For example, the Lenovo 14p
               | lineup, but there are many others.
               | 
               | Depending on where you live, there may be some supply
               | issues, especially if you are looking for a model with an
               | NVidia 3000 series GPU.
        
               | rowanG077 wrote:
               | That's not really the same form factor. It's at least 20%
               | heavier and much more thick and larger. The same form
               | factor would be something like a Dell XPS 13 or surface
               | pro. But those are not offered with Ryzen CPUs.
        
               | sudosysgen wrote:
               | It is less than 10% heavier (1.4kg vs 1.29kg) and is
               | 0.9mm thicker. It is about 22mm wider and 6mm deeper,
               | with a screen 18mm larger in diagonal.
               | 
               | Unless you're _really_ being pedantic the two are of the
               | same form factor. Maybe you are comparing the Intel
               | ThinkBook 14? That one is significantly heavier and a bit
               | thicker.
               | 
               | If an increase in size of around 5% is too much, there
               | are smaller laptops with the same processor family.
        
               | [deleted]
        
               | rowanG077 wrote:
               | Which computer in the same form factor as the air is as
               | capable or better? All of them are throttling messes. AMD
               | is better then Intel but they still throttle.
        
               | sudosysgen wrote:
               | The high end Ryzen 5000 series processors even when
               | throttled to their lowest continuous speed still
               | outperform the M1 Macs in multicore. Having twice the
               | cores makes a huge difference.
        
             | rowanG077 wrote:
             | But why not call out the specific niche then? Pro does not
             | equal high demands. And audio has very different demands
             | then 3D work for example. In fact for audio work the M1 is
             | perfect hardware wise.
        
               | coldtea wrote:
               | There are pros that don't even need a computer.
               | 
               | We're talking here about pros in the context of
               | "increased hardware demands".
               | 
               | This has little to do with "Pro" in the product name or
               | not, nor with them being more professional than other
               | working people.
        
               | rowanG077 wrote:
               | The M1 Macbook pro is better then the 16 inch intel
               | Macbook pro. I'm not sure it gets more "pro" then this.
        
               | samatman wrote:
               | For Apple, the core of "pro" is audiovisual
               | professionals.
               | 
               | I mean, really, it just means "the expensive one", as in
               | AirPods Pro, but sticking to Macs for a second: if your
               | job is video editing, or publishing, the bigger and nicer
               | screen is going to trump a faster processor and better
               | battery life. The (much) better speakers are also a big
               | plus.
               | 
               | Smart users in that category are holding off new
               | purchases, if they possibly can, until the M2
               | (presumably) 16" MBPs drop. Especially if the rumors hold
               | and it comes with an onboard SD card reader.
        
               | michelb wrote:
               | The M1 is fine for a lot of workloads but the current M1
               | macs are not suitable for heavy work. Regarding niches;
               | video work, audio work, ML, compiling stuff larger than
               | simple projects, etc. The current M1 macs start to break
               | down on a lot of medium sized workloads due a lack of
               | RAM. So in my view, pro machine = >32gb ram, better gpu
               | performance, better multicore performance.
        
         | shawnz wrote:
         | You can simply boot to the internet-based recovery image and
         | reinstall or access your data from there, so there is no
         | concern about trashing your installation.
         | 
         | Furthermore I don't see any reason to think that OP's issues
         | are to do with the hardware or that we will have to wait for
         | the next hardware model to have these issues resolved. It seems
         | like a simple OS-level software bug to me.
        
           | philistine wrote:
           | Oh i did trash my installation. I somehow didn't have
           | permissions to reinstall from internet recovery. I had to
           | plus another Mac and use Configurator to restore it.
        
             | shawnz wrote:
             | Try erasing all the existing volumes and create a new one
             | before starting the installation next time. That sounds
             | like the message you would get if you are trying to install
             | onto the recovery partition.
             | 
             | EDIT: According to other posts there are in fact some
             | volumes on M1 Macs where if deleted, you will need to do a
             | DFU mode recovery. So perhaps don't actually delete all
             | existing volumes on an M1
        
       | marcan_42 wrote:
       | The M1 boot process is _very_ different from Intel macs. In fact,
       | they do not support external boot disks at all, by design. This
       | is because the built-in firmware is extremely minimal, and does
       | not contain drivers for anything but the internal SSD. It doesn
       | 't even have a keyboard driver, or any kind of GUI other than
       | showing the Apple logo and "Entering startup options" text, and
       | some error screens. All of this is by design, for security - UEFI
       | is an enormous hairball of code, especially on Intel macs, and
       | almost impossible to secure properly for that reason.
       | 
       | When you boot into the "Startup Options" menu, you are booting
       | into a special macOS partition in the internal SSD. M1 Macs use
       | macOS as the moral equivalent of the UEFI setup menu. That boot
       | picker that looks like the UEFI boot picker on Intel Macs? Yeah,
       | that's a full-screen app on macOS made to look similar.
       | 
       | So how does external boot work?
       | 
       | The "blessing" process done by the Startup Options screen
       | involves copying the entire macOS Preboot partition - iBoot2 OS
       | loader, Darwin kernel, auxiliary CPU/device firmwares, device
       | tree, and some additional stuff - to the internal SSD. It then
       | creates a local, signed boot policy that allows system firmware
       | to boot this macOS install.
       | 
       | You aren't booting from an external disk. You are booting from
       | the internal SSD, with the root filesystem on the external disk.
       | 
       | Additionally, the integration of the macOS user credentials with
       | the SEP means that you can't "just" take an install made on
       | another machine and use it on a separate one. It involves
       | importing user credentials into the local machine. This process
       | isn't implemented properly yet.
       | 
       | As you might expect, this entire mechanism introduces a ton of
       | corner cases around updates, boot selection, etc., and it is
       | still very buggy and broken. The M1 launch was, when you look at
       | details such as this, very obviously rushed.
       | 
       | Further reading for those interested:
       | 
       | https://github.com/AsahiLinux/docs/wiki/M1-vs.-PC-Boot
       | https://github.com/AsahiLinux/docs/wiki/SW:Boot
       | https://github.com/AsahiLinux/docs/wiki/SW%3AStorage
       | 
       | I'm actually eagerly waiting for Apple to fix this in future
       | system firmware releases, because my plan for installing Asahi
       | Linux for end users with a minimal amount of fuss is to abuse the
       | mechanism to adopt foreign macOS installations. This elides the
       | current need to have a completely wasted, 60+GB macOS install as
       | a dummy to actually launch Linux (we could clean it up and resize
       | it to get the space back, but it still makes for a very annoying
       | install process that I'm hoping to avoid).
       | 
       | On the plus side, this dual-booting mechanism is very cleverly
       | designed to separately secure _different_ OSes, so you do not
       | need to downgrade security on your machine to install an unsigned
       | OS like Linux. It is a separate OS with a separate security
       | policy. You can keep your macOS install fully secure, and capable
       | of running iOS apps and other actions that require secureboot,
       | and install Linux (or another macOS with a custom kernel, kexts,
       | etc) in parallel, completely unintrusively. So kudos to Apple for
       | designing this whole thing, and for opening it up for us to use
       | :)
        
         | spijdar wrote:
         | > You aren't booting from an external disk. You are booting
         | from the internal SSD, with the root filesystem on the external
         | disk.
         | 
         | So this means that the life of all M1 Macs is locked to the
         | life of the internal storage, as the (inevitable) drive failure
         | will render the whole computer unusable?
        
           | db48x wrote:
           | Except presumably for replacement with identical hardware.
        
           | marcan_42 wrote:
           | Yes. This is also the case for just about every other
           | computer out there, as chances are most PCs will end up
           | writing to UEFI variables on every boot for something or
           | other anyway, and those are stored in Flash memory too, which
           | has a finite endurance. That should be NOR flash, which
           | should have higher endurance than the NAND in SSDs - but we
           | also don't have any numbers on Apple's SSD endurance, so it
           | would be premature to speculate that this is going to be a
           | real problem in non-pathological use cases, and that the
           | machine won't in practice die first of other causes.
           | 
           | Strictly speaking, the things can boot off of DFU (USB device
           | mode) too, but to make that useful for regular boot you need
           | to ask Apple, as currently you cannot boot a normal OS like
           | that as far as I know, only their signed restore bundles
           | (which is how you fix an M1 Mac if you wipe the SSD).
        
             | Wowfunhappy wrote:
             | Would it be possible to replace the internal SSD? Possibly
             | by setting some laxer security policy before the original
             | one dies?
        
               | plussed_reader wrote:
               | Very do-able on 2015 MacbookPros; can't imagine it's that
               | different on the M1 mobo.
        
               | tenacious_tuna wrote:
               | I am certain the internal SSD is soldered on--I believe
               | the whole M1 motherboard is an SOC.
        
             | spijdar wrote:
             | While technically speaking yes, eventually the firmware
             | flash will fail, I'm not sure bad UEFI variables will
             | actually prevent the system from booting, since the rest of
             | firmware should be fine. I've gotten systems to boot with
             | totally borked UEFI flash space.
             | 
             | It is being nitpicky on my part, but I think we're reaching
             | the point where these machines could be expected to last
             | long enough for SSD weardown to become a real issue, even
             | with current flash tech. While this has theoretically been
             | a problem for the past 5 years now, it's a bit
             | disappointing to learn that now you can't use an external
             | drive in the event of the (irreplaceable) internal drive
             | failing.
        
               | floatboth wrote:
               | Raw EDK2 doesn't really need variables at all (in fact if
               | you use it as a coreboot payload, persistentce is not
               | implemented whatsoever, at least as of.. some time ago).
               | 
               | Various crap bolted on by AMI and the OEMs... well, YMMV
               | - remember these laptops where someone did rm -rf with
               | mounted efivarfs on Linux and that _bricked_ it because
               | it just refused to boot without the variables :D
        
               | spijdar wrote:
               | I can believe that sadly :/ UEFI implementations range
               | from pretty good to absolute crap. My newest Dell has at
               | least been mostly decent, but an older Dell has so many
               | issues with the firmware, it's unbelievable.
               | 
               | Not that it (worn out flash) is gonna be a problem in
               | practice, anyway. Neither will the M1's inability to boot
               | without the internal drive. Like Marcan said, it's not
               | really likely to die in realistic use within a pretty
               | long lifespan, I just find these sorts of
               | shortcomings/regressions ... disappointing. I get the
               | various reasons _why_ , it's just annoying.
        
               | marcan_42 wrote:
               | That depends on the implementation. For example, I've
               | seen many PCs exhibit a behavior where after a major
               | hardware change, usually CPU or RAM, the system boots,
               | shuts down, then boots again automatically. Presumably
               | after discovering the change it wrote some variables
               | describing it, then rebooted. Without the ability to
               | persist that information, I would expect it to loop
               | forever.
        
       | s_dev wrote:
       | External SSD is my default setup. I encourage it in the office as
       | well. Even my gaming machine is setup at home this way. When
       | popping over a mates I often just plug it out and stick it in to
       | their machine.
       | 
       | It's very useful to be able to seperate data from the hardware.
       | If something is wrong with a machine I can just plug straight in
       | to another one. An SSD is much easier to carry than a laptop.
       | 
       | The other problem with internal hard drives is when they get
       | stuck inside e.g. with MacBooks being sealed these days. External
       | SSDs can offer great flexibility and a trade off worth
       | considering. I can imagine people having security concerns etc.
       | 
       | Disappointing to hear this about the new M1s.
       | 
       | I recommend people interested in dipping their toes into Linux
       | Gaming trying this approach:
       | 
       | https://www.easyuefi.com/wintousb/
       | 
       | https://rufus.ie/
        
         | suyash wrote:
         | I've been using external disk as my main macOS too and the only
         | downside is the worry cable would snap out which it did a few
         | times when I moved laptop around and crashed everything. Other
         | than that, great way to upgrade my MBP with 1TB disk without
         | needing to buy new MBP.
        
         | sirius87 wrote:
         | Folks doing this need to be careful not to plug their disk into
         | a machine with a different OS.
         | 
         | If the disk is plugged into an already booted system and the OS
         | doesn't recognize the filesystem format, I believe macOS and
         | Windows display a prompt to format the disk, which someone may
         | accidentally click.
        
         | reaperducer wrote:
         | _When popping over a mates I often just plug it out and stick
         | it in to their machine._
         | 
         | This was one of the touted technical uses for the first
         | (Firewire) iPod. Apple had a notion that people could carry an
         | iPod with them, and then boot any Mac from it and start working
         | right where they left off.[1] This is why Xserves had a
         | Firewire port on the front.
         | 
         | [1] As a point of interest, this used to also exist in the
         | radio industry. Certain brands of control boards had
         | "personality cards" that could be tuned[2] to a particular D.J.
         | Then when the D.J. had to work from another studio, or
         | remotely, he could pop his personality card into the control
         | board and it would be preset to him.
         | 
         | [2] And by "tuned," that meant tuned for his voice[3], to make
         | it sound the way he, or his program director, wanted it to
         | sound.
         | 
         | [3] Even more interesting: Though these were circuit boards,
         | the tuning was done mechanically, and by hand. They were a
         | series of potentiometers covering different frequency ranges.
        
           | grishka wrote:
           | Oh the glorious offline-first software and hardware. I miss
           | it. Today this would've been handled through "the cloud",
           | requiring an account, a consent to tracking and analytics, a
           | monthly subscription, and a reliable high-speed internet
           | connection.
        
           | bangonkeyboard wrote:
           | "Home on iPod" wasn't a full bootable OS X, just the user's
           | Home directory. The feature was also canceled before release,
           | likely due to performance or durability limitations of the
           | iPod's micro hard drive.
        
         | dukeofdoom wrote:
         | I actually started doing this on my TVs. They have usb ports. I
         | bought a 16GB usb stick. And I just did youtub-dl to download a
         | bunch of workouts. And then use roku app on the TV to play
         | them. Saves time, and no youtube ads.
        
         | tinyhitman wrote:
         | What interface do you use (USB/eSATA, etc)?
         | 
         | And you mention gaming setup, assuming windows, is this as
         | portable as you make it sound? No weird hardware-dependent
         | issues?
        
           | checkyoursudo wrote:
           | A couple of years ago I used to run a qemu Linux-
           | host/Windows-guest with PCI pass-through for GPU/SSD/etc.
           | 
           | I could either boot the Windows install directly from the
           | SSD, or I could boot Linux and then run the same install in
           | qemu, without issue.
           | 
           | I think there used to be more problems if you changed the
           | hardware too much from the original install. Like, if you
           | changed your motherboard (which the above would do of
           | course), then you couldn't run the same install. But I don't
           | think that's as much of a problem anymore?
           | 
           | This was of course not an external SSD, so I don't know how
           | that changes things, if at all.
        
             | tinyhitman wrote:
             | Cool! I used to run a similar setup, when I started out I
             | passed through the hardware. But when things were running
             | smoothly I never booted back into windows natively (Wasn't
             | planning on this use-case).
             | 
             | Nice to hear that it is possible. I feel like MS
             | essentially gave everyone the wrong idea about OSes dealing
             | with hardware changes.
        
         | 1vuio0pswjnm7 wrote:
         | "It's very useful to be able to seperate data from the
         | hardware."
         | 
         | I have been doing this for decades, but I do it with USB
         | sticks, not SSDs, with NetBSD, not Windows. After boot I can
         | pull out the stick, freeing up the USB port for something else.
         | 
         | I would be interested if I coul do the same with Windows but it
         | does not seem as straightforward. I know it is _possible_ but I
         | also know there is a good chance I would never get it to work.
         | 
         | For example, the EasyUEFI link you provided suggests I need to
         | purchase software, the software only runs on Windows, Windows 7
         | is not truly portable and the authors are not clued in to the
         | idea of separating data from hardware:
         | 
         | "We recommend that you use Hasleo BitLocker Anywhere to encrypt
         | Windows To Go drive to keep your data safe. If you want to
         | upgrade Windows To Go to Windows 10 October 2020 Update
         | (Windows 10 20H2), please go to Windows To Go Upgrader."
         | 
         | If only there was a way I could buy Windows on a stick instead
         | of having to buy a computer with pre-installed.
        
           | abc_lisper wrote:
           | >>> After boot I can pull out the stick, freeing up the USB
           | port for something else
           | 
           | Does this mean the entire OS is loaded into memory? Is this a
           | NetBSD thing?
        
             | 1vuio0pswjnm7 wrote:
             | A "miniroot" is stored in the kernel, indeed the entire OS
             | is loaded into memory. Other BSDs and Linux have used, and
             | may still use, similar approaches in some cases. (For
             | example, BSD install media.) This is old hat but reliable.
             | What is amazing is that you still see people in 2021, when
             | most computers have ample amounts of memory, complaning
             | about "disk" issues, e.g., people try to use SD cards as a
             | "hard drive" for RPis.
        
               | bitwize wrote:
               | The Raspberry Pi foundation wants you to use Visual
               | Studio Code, which means you want to free up RAM. A file
               | system on SD that's mounted read only on boot might be a
               | good call, with /home on an external USB.
        
             | bitwize wrote:
             | It can be done with Linux or any OS that has a RAM-based
             | file system. And with machines coming with gigabytes of
             | memory, the installation supported by a RAM FS can be very
             | complete indeed. See Puppy Linux as an example of a distro
             | that can run from RAM.
        
         | shawnz wrote:
         | One of the major advantages of the M1 hardware is that the
         | storage controller for the SSD is directly integrated into the
         | CPU. You would be losing a big part of that performance
         | advantage by using an external OS volume.
        
           | chungus_khan wrote:
           | That isn't true. There wouldn't be a performance advantage to
           | that at all (the limiting factors in storage performance have
           | nothing to do with motherboard trace length, which has a
           | negligible impact on performance in general), and the M1 Macs
           | have fairly ordinary SSD performance.
        
         | space_rock wrote:
         | What about driver differences? Plug into a computer with Nvidia
         | card from a computer without...
        
           | gogopuppygogo wrote:
           | Mac installs support all compatible Mac hardware for that OS
           | version.
        
           | stefan_ wrote:
           | On x86, that's the reality. I recently went Intel CPU & AMD
           | GPU to AMD CPU & Nvidia GPU and just booted straight into my
           | old Windows system, no problem at all.
           | 
           | But on anything ARM based? The whole ecosystem _doesn 't give
           | a fuck_. Everything is hyperspecific for _one_ platform
           | exactly. At one point, the Linux kernel had thousands of
           | board source files that specified exactly what hardware your
           | cursed ARM board had. Then they invented device tree but
           | frankly the situation has barely changed, don 't expect to
           | ever build a generic ARM image for anything.
        
             | floatboth wrote:
             | You are describing specifically "embedded junk" (which
             | includes the M1, sorry Apple) not literally "anything ARM
             | based". SBSA-compliant platforms boot with UEFI+ACPI, using
             | fully generic DSDT descriptions for PCIe (ECAM) and USB
             | (XHCI). Speaking of GPUs, quite common for them to have
             | QEMU in firmware to run the x86-compiled EFI GOP driver
             | straight from the card's ROM and get video output before
             | the OS.
        
               | heavyset_go wrote:
               | It's cheaper to use custom ARM boards than it is to build
               | hardware that is SBSA-compliant, so consumers can expect
               | that most, if not all, of their ARM devices are not SBSA-
               | compliant.
        
         | cehrlich wrote:
         | I've never done this, so my concern might be a total non-issue.
         | 
         | But how do you prevent the external SSD accidentally becoming
         | unplugged when you're doing this with a laptop? And what would
         | actually happen if that did occur?
        
           | bee_rider wrote:
           | I do this with a desktop, so the plug thing is a non-issue
           | really, but velcro is always an option if you don't care
           | about aesthetics.
        
           | sschueller wrote:
           | You could get something like this:
           | https://www.amazon.com/PCIe-NVMe-Mobile-External-
           | Drive/dp/B0...
        
           | aloer wrote:
           | I'm using a Samsung t5 via usb c on my MacBook and I'd
           | confidently say it's impossible to accidentally unplug. Not
           | sure if they made the plug like that on purpose or not but
           | it's definitely harder to remove than most other usb c plugs.
           | Even after more than a year of use
           | 
           | What I've also seen some companies do is simply duct tape the
           | ssd to the laptop lid so they can walk around freely to
           | meeting rooms etc.
           | 
           | At home I don't need that
        
             | reasonabl_human wrote:
             | Are you using it as an external boot drive or just as
             | additional storage? I've seen people use it for storage but
             | the parent comment is the first I've heard of potentially
             | using this as it's own OS..
             | 
             | Perhaps useful for dual-booting between personal and work
             | installations, considering MacBooks are sealed with one
             | drive?
        
               | aloer wrote:
               | Yeah exactly. I had to get my work MacBook repaired a few
               | times last year and since I'm working from home I just
               | mirrored the internal ssd to the t5 and booted from it on
               | my private Mac.
               | 
               | This way I kept all the company settings and programs
               | working in a way that a time machine restore couldn't do.
               | 
               | Works just the way you would expect from an internal ssd
               | and switching takes less than two minutes if necessary
        
               | ArchOversight wrote:
               | My companies MDM software would freak out if I did that.
               | So much of it is tied to the specific serial number of
               | the machine, as well as various baked in management of
               | push notifications for profile updates and the like being
               | tied to the device itself through Apple.
        
             | fpoling wrote:
             | The duct tape even does not look ugly when you work as it
             | is hidden behind the lid.
        
           | s_dev wrote:
           | It has happened to me -- you lose your work if it plugs out
           | but the drive is nearly always recoverable. Think of it as a
           | power outage.
        
           | adrian_b wrote:
           | It would be annoying, so you should better avoid that.
           | 
           | Currently this is the weak point of using external bootable
           | SSD's. Because of that, I prefer the SSD's where the
           | Thunderbolt/USB cable is captive at the SSD end, as then
           | there are less connections that can be unplugged
           | accidentally.
           | 
           | What I would like is to have in the laptop a CFexpress memory
           | card slot.
           | 
           | The CFexpress memory cards have a PCIe electrical interface,
           | but they are mechanically identical with the older Sony XQD
           | cards, i.e. they are solid, rugged, not flimsy like the SDXC
           | memory cards, and they allow a very large number of
           | insertion/extraction cycles.
           | 
           | If the laptops would have such card slots and if SSD's would
           | be available at a reasonable price in this format, then there
           | would not remain any reason to use non-removable SSD's. The
           | current CFexpress specification is based on PCIe 3.0, but
           | future versions can be updated to PCIe 4.0, like the internal
           | M.2 SSD slots of the latest laptops.
        
             | WesolyKubeczek wrote:
             | > If the laptops would have such card slots and if SSD's
             | would be available at a reasonable price in this format,
             | then there would not remain any reason to use non-removable
             | SSD's.
             | 
             | A gentle reminder that you live in a world where SSDs on
             | some laptops are not removable at all, as are batteries.
             | And I'm leaving out minutiae like RAM.
             | 
             | I'm just not seeing it as possible, how would you plan the
             | obsolescence of such devices?
        
               | toast0 wrote:
               | If it's easier to take your data drive from one laptop to
               | the next, it's no longer a end user problem when the
               | laptop needs to be thrown away at the end of each season.
               | 
               | Yes, it's a shame you can't charge a 10x markup on the
               | storage the end user takes with them, but you can still
               | charge a 10x markup on the built in storage that's non-
               | removable and whose failure still blocks booting
               | (necessitating replacement of the whole thing, naturally)
        
             | dylan604 wrote:
             | We're well past having card slots on laptops in the Apple
             | realm. Rumor mill suggested possibly getting ports back on
             | a refreshed MacBookPro, but I am not holding my breath.
             | 
             | For those not using Apple laptops, this might be a thing,
             | but I still doubt it's something manufactures will see a
             | lot of demand.
             | 
             | My favorite has been the USB memory sticks that are the
             | same physical size as a bluetooth dongle. Since they are so
             | low profile, the chances of them coming unplugged are
             | pretty damn slim. The only draw back was they are pretty
             | small in capacity for trying to run an OS.
        
             | kop316 wrote:
             | You are describing something somewhat similar to this:
             | 
             | https://www.crowdsupply.com/eoma68/micro-
             | desktop/updates/sta...
        
             | NathanielK wrote:
             | Not quite the same, but there's a product being developed
             | to adapt M.2 2242 NVMe drives to Expresscard, the other
             | hotpluggable PCIe standard. Most expresscard
             | implementations are only a since lane of PCIe v2, though
             | some of the new "P" series thinkpads support v3. Being a
             | single lane limits it compared CFexpress, but it's still a
             | bump over AHCI drives.
             | 
             | Thinkpads up to 2013 also had a tool-less removable disk
             | drive that allows for hot swapping 2.5" SATA drives in
             | seconds while keeping them safe inside. This has been
             | abandoned with the obsolescence of optical drives though.
             | 
             | > The CFexpress memory cards have a PCIe electrical
             | interface, but they are mechanically identical with the
             | older Sony XQD cards, i.e. they are solid, rugged, not
             | flimsy like the SDXC memory cards
             | 
             | I agree, though with SDExpress becoming standard soon there
             | is a much realler possibility of future laptops having pcie
             | microsd slots, which might be good enough if you can find a
             | durable model.
             | 
             | [1] https://thinkmods.store/products/expresscard-to-nvme-
             | adapter
        
             | awiesenhofer wrote:
             | Wow, I didnt even know these existed, thanks for
             | mentioning! Having these CFexpress cards as an option
             | instead or next to an SD card reader on laptops would be
             | great, for compact backups alone. But looking up details
             | and pricing I get a huge DAT vibe: excellent product,
             | limited users makes for expensive media and even less
             | adoption...
        
         | adrian_b wrote:
         | I agree. Already for many years I work almost only on external
         | (bootable) SSD's, for exactly the same reasons.
        
         | rock_artist wrote:
         | It works nicely if you don't use commercial apps that uses
         | device identifiers for activation.
         | 
         | For such scenarios common by media creators external disks fail
         | to "just" plug. Some apps uses dongles or allow activating to
         | usb sticks. But still it's the exception.
        
         | mobilemidget wrote:
         | I can only assume your external disk is encrypted. Does that
         | work fine with booting in every machine you tried?
        
           | s_dev wrote:
           | I'd only bother to encrypt work machines -- I don't see why
           | it wouldn't work. My gaming setup -- I'd definitely not
           | bother.
           | 
           | Not every machine is a guaranteed boot. It depends on MBR/GPT
           | etc and whether UEFI is disabled in the BIOS and other
           | configurations. However generally yes, they will. I've even
           | have setups where the SSD would would have
           | macOS/Windows/Linux. Much older motherboard pre-2012
           | generally don't like this setup and it can be v.slow.
        
             | reasonabl_human wrote:
             | I have enough trouble dual-booting encrypted internal disks
             | on the same machine... any changes to the TPM, or say
             | booting one disk as a virtual machine from within the other
             | disks OS running natively, breaks all AAD and windows hello
             | authentication for me. Have to remove accounts and add them
             | back in from settings on windows 10. So I'd be quite
             | surprised if you've figured out a seamless way to boot an
             | encrypted disk on multiple machines...
             | 
             | For example, with bitlocker, won't you need to enter the
             | recovery key when trying to boot from a new machine? And
             | have to sign out and back in to all relevant OS level
             | accounts? Even then I face authentication issues at times
             | 
             | I really would like this to work seamlessly because moving
             | my internal SSD work disk to an external one would be far
             | safer than lugging it around inside my personal laptop all
             | the time. But the work disk has to be encrypted...
             | 
             | Also, for hardware compatibility's sake, I'd think Linux
             | would be a far superior daily driver OS to 'multi-hardware
             | boot', considering relevant drivers are loaded from kernel
             | on boot rather than selectively pre-installed at OS
             | creation time for that one device, increasing plug and play
             | compatibility
        
               | fpoling wrote:
               | If you cannot have fully encrypted setup, then you can
               | consider encrypting at least most of data.
               | 
               | At work due to remote work I cannot have fully encrypted
               | disc with Windows as I have to reboot remotely. So I left
               | a small enough partition for Windows, then created
               | another partition for my data that I encrypted with
               | strong password in Bitlocker. Then I symlinked my user
               | directory from C:\Users\UserName to a directory on D: and
               | created an extra account that I use after reboot to
               | unlock the encrypted disc with my data.
               | 
               | This is not ideal, as Windows still may store my data on
               | C:\, but if one disables virtual memory, it is a
               | reasonably secure setup.
        
               | codys wrote:
               | Bitlocker can be configured (via manage-bde on the
               | cmdline, iirc) to use a passphrase and not use the TPM at
               | all.
        
               | reasonabl_human wrote:
               | Yeah for unlocking it within a host OS as a data disk,
               | not for booting from it... you can set auto unlock at
               | boot or a pin to boot, both of which use the TPM
               | 
               | But try move a bootable bitlocker encrypted disk to new
               | hardware and you'll have to enter the recovery key
               | 
               | I would really like to be wrong about this since it would
               | make my life much easier, but this understanding is based
               | on experience using multiple work machines with encrypted
               | boot drives every day :(
        
               | kryogen1c wrote:
               | > Yeah for unlocking it within a host OS as a data disk,
               | not for booting from it...
               | 
               | this is not true. you can configure bitlocker with or
               | without TPMs.
               | 
               | just google it. also the doc for the powershell command
               | talks about it in the establishing a key protector
               | section
               | 
               | https://docs.microsoft.com/en-
               | us/powershell/module/bitlocker...
        
               | reasonabl_human wrote:
               | Oh wow, thank you! Should've known to head straight to
               | the docs instead of searching phrases online. Now to
               | spend the next day backing everything up and configuring
               | passphrase on boot...
        
         | protoman3000 wrote:
         | How do you boot Windows from USB without using third party
         | tools?
        
           | adrian_b wrote:
           | I have no idea. That is why I boot Linux from Thunderbolt or
           | USB and for the few Windows programs that I need I use either
           | Wine or a Windows VM.
        
           | userbinator wrote:
           | Look up WinPE. It's a lightweight "live CD/USB" version of
           | Windows that can be run entirely in RAM. A full "portable
           | Windows" install can be made from it. AFAIK all the third-
           | party tools do is automate the process of copying thousands
           | of system files and also act as a boot manager.
        
           | s_dev wrote:
           | WinToUSB is $50 but they allow you to do Windows Home and MBR
           | partitions for free. Rufus and Disk Utility for Linux/mac OS
        
         | Abishek_Muthian wrote:
         | I agree with your reasoning, especially since external SSD have
         | made it safer to carry physically as opposed to external HDD.
         | 
         | But I mirror my internal NVMe SSD to external SSD as the
         | performance benefits of the former matters for me most of the
         | time and when needed bootable external SSD is available at
         | disposal.
         | 
         | On macOS(not M1), Carbon Copy Cloner could create bootable
         | clones of the disks. But I'm out of macOS for good as changes
         | in Big Sur was too much for me, No offense to those who like
         | it; but it seemed like a _unicorn poop_ for me. Mojave was the
         | last version which preserved the essence of macOS IMHO.
         | 
         | Now I'm back to Linux, hopefully btrfs(snapshots) + Timeshift
         | should recreate the same workflow.
        
         | valine wrote:
         | What about performance concerns? This sounds unbearably slow,
         | especially for someone accustomed to an NVME SSD. Not sure why
         | you would do that to yourself when cloud backups are an option.
        
           | adrian_b wrote:
           | I have been using for several years bootable Thunderbolt 3
           | SSD's (on Linux).
           | 
           | As those are equivalent with 4 PCIe 3.0 lanes, exactly like
           | the internal M.2 type M SSD slots, there is no performance
           | difference.
           | 
           | Only the latest laptops with Tiger Lake, and the laptops with
           | Ryzen 5xxx to be introduced soon, have PCIe 4.0 M.2 slots, so
           | they will be able to have faster internal SSD's.
           | 
           | I expect that the interconnection standards for external
           | devices will also continue to be improved, restoring parity
           | with the internal devices.
        
             | 1996 wrote:
             | > As those are equivalent with 4 PCIe 3.0 lanes
             | 
             | Can you suggest some brands or models?
        
               | rz2k wrote:
               | Tom's Hardware seems to have a good list from January 1
               | this year: https://www.tomshardware.com/reviews/best-
               | external-hard-driv...
        
           | gogopuppygogo wrote:
           | I tried this for a bit and noticed a huge performance drop.
           | Also noticed system freezing.
           | 
           | I have an NVME 2.0TB drive in a USB-C enclosure and while
           | fast as an external this is not fast enough for booting and
           | running the dozen or so apps I keep open on my MBP.
           | 
           | YMMV if you don't act as a power user.
        
             | lnanek2 wrote:
             | USB-C is super slow for this. You need to use Thunderbolt
             | NVME enclosures which can run the NVME at PCIe 3.0 x 4
             | speed. I have 5 and RAID them together, which handily beats
             | the internal drive for speed by about 2x.
        
             | rfoo wrote:
             | > USB-C enclosure
             | 
             | Keep in mind that USB-C != Thunderbolt 3. Yes, the latter
             | also physically connects to a USB-C form port, but it's
             | totally different. It's quite confusing and sad.
        
               | Hamuko wrote:
               | Was USB 4 gonna solve that or was that just me dreaming?
        
               | samatman wrote:
               | USB 4 is basically just Thunderbolt 3. Standards bodies
               | being what they are, it's more complicated than that, but
               | not by much.
        
           | netsharc wrote:
           | I think OP is talking about booting from an operating system
           | installed on the SSD, so I'm not sure how you can replace
           | that with "cloud backups".
           | 
           | This sounds like an ad, but Sandisk has USB 3.2 flash drive
           | with NVMe inside, that according to this has up to 2 GB/s
           | read speed: https://www.amazon.com/SanDisk-Extreme-Portable-
           | External-SDS...
           | 
           | I used the version 1, not NVMe, which can only do half that
           | speed, but I found it plenty fast.
        
             | fragmede wrote:
             | The technical details may differ between if my data is
             | stored on an SSD I'm accessing locally that I booted from,
             | vs if my data is stored in the cloud and I'm accessing it
             | via a web browser, but at the end of the day, I have access
             | to my files. The technical differences have many practical
             | ramifications (eg disk speed), but they are sufficiently
             | practically equivalent for many different use cases. We see
             | this with Chromebooks, where they will never be a full
             | replacement for every windows machine. There is a large
             | reason they've gained marketshare, however.
        
             | Dylan16807 wrote:
             | Both versions have NVMe inside them, actually.
             | 
             | Not that that means anything for performance. NVMe just
             | means that it uses PCIe.
             | 
             | Since the external port is USB, the internal use of NVMe is
             | actually a downside. The drive actually has two separate
             | circuit boards inside. One of them takes up space and power
             | just to convert NVMe to USB, and wouldn't exist in a better
             | design.
             | 
             | https://i.imgur.com/6oPiOls.jpeg
             | 
             | https://static.tweaktown.com/content/9/2/9280_08_sandisk-
             | ext...
        
           | lm28469 wrote:
           | Not so long ago SSDs didn't exists and people were using
           | their PC just fine. Today's high performance portable SSD are
           | miles ahead of the 10000rpm "fast" internal HDDs from back in
           | the days
        
             | oceanplexian wrote:
             | Software has bloated so much that users having an SSD is an
             | assumption. In fact a 2.5 SATA SSD is almost unbearable on
             | a modern machine for gaming, etc. since M2/NVME showed up.
        
               | cptskippy wrote:
               | No it isn't. My gaming PC has a 2TB SATA SSD that I store
               | all my games on and it's more than fine.
               | 
               | Many people still use HDDs for game storage.
        
             | bee_rider wrote:
             | Kinda yeah, but just to set expectations -- if you want to
             | do an external hard drive as your main drive, just get a
             | thunderbolt drive. You might be able to massage a usable
             | experience out of USB, but thunderbolt is more or less
             | equivalent to an internal drive.
        
           | lupire wrote:
           | Computers run mostly from RAM and network. Unless you are
           | doing heavy disk work, nvme isn't a big deal. You can use
           | internal disk for temporary projects (compiling, video
           | editing) and then copy the snapshot to external at end of
           | day.
        
             | abrowne wrote:
             | Tell that to my work iMac with a HDD (not my choice) and a
             | new enough OS to require APFS. The only programs I
             | typically have open are Chrome and a music player, and it
             | freezes randomly, and Chrome is constantly waiting on
             | cache.
        
               | wheybags wrote:
               | Get a new employer...
               | 
               | (Alternatively, if you really can't switch job, just buy
               | an ssd yourself)
        
               | abrowne wrote:
               | It's not that bad ... for what I'm doing, and I can do
               | something else when the computer stalls. I've thought
               | about an external TBT SSD, but doesn't seem worth it yet.
        
               | wheybags wrote:
               | I dunno man, ssds are pretty basic fare these days. They
               | have been standard for about a decade now. If an employer
               | refuses to give their developers ssds to work off, that's
               | a massive sign of disrespect IMO.
        
           | s_dev wrote:
           | I haven't noticed any performance degradation which is
           | counter intuitive because I really expected there to be one.
           | The Samsung T5 - T7s have been great in my experience. As for
           | the cloud .. well that has it's own challenges too. Currently
           | I'm trying to deGoogle myself and not doing a great job at
           | it.
           | 
           | To address any conventional SSD vs NVMe SSDs performance gap
           | maybe consider and external NVMe SSD!
        
             | shawnz wrote:
             | The internal SSD in M1 Macs is actually superior even to
             | NVMe, since the controller is integrated directly into the
             | CPU.
        
               | mhh__ wrote:
               | [Citation needed]
        
               | vetinari wrote:
               | It has about the same performance as a normal PCIe 3.0 4x
               | NVMe drive.
        
               | buildbot wrote:
               | Even latency/at low queue depths? I'd expect it to have
               | stunning low latency compared to standard nvme honestly.
        
               | Dylan16807 wrote:
               | The analog parts are the slow parts.
               | 
               | PCIe costs you less than a microsecond of latency. A good
               | SSD has 60 microseconds of latency. You're not going to
               | notice any difference from moving the controller.
        
               | [deleted]
        
         | NikolaNovak wrote:
         | I would love to do that; but Windows (yes yes I know:) seems to
         | intentionally block normal installation to external SSDs; and
         | all the workarounds I've tried so far have removed all the
         | convenience factors :|
        
         | intrasight wrote:
         | >When popping over a mates I often just plug it out and stick
         | it in to their machine.
         | 
         | I would have assume that this would not work unless the
         | hardware was the same - due to device drivers, etc.
        
           | donut2d wrote:
           | Between Macs with macOS, this usually works fine (except with
           | older hardware that is not supported by the OS on the
           | external drive). Can't say for Windows.
        
           | heavyset_go wrote:
           | This might be the case for Windows, but with Linux, most
           | drivers are already distributed with the kernel and can be
           | dynamically loaded and unloaded depending on what hardware is
           | discovered while booting or afterwards.
        
           | bee_rider wrote:
           | It is pretty much just an issue of having the right graphics
           | drivers.
        
           | s_dev wrote:
           | I would have expected that as well but found in general the
           | process to be pretty seamless.
           | 
           | I should probably mention I just stumbled on to this approach
           | rather than having forged it through clever thinking -- it
           | was originally due to a faulty motherboard burning out
           | internal HDDs consitently. So I HAD to opt for an external
           | drive and once I did the going back made little sense as it
           | just imposed restrictions I didn't want anymore.
        
         | sys_64738 wrote:
         | The M1 Mini is so small I can pack it and take it with me.
        
       | carlosrg wrote:
       | Slightly off-topic but I remember when system updates on Macs
       | were handled much better than for example Windows. I think that's
       | no longer the case: you can't download standalone updates (the
       | .pkg) anymore, and installing them feels like you're installing
       | the entire OS (even a minor release like 11.2.1 needs a several
       | gigabyte download and takes a long time to install).
        
         | CharlesW wrote:
         | I believe you're right that you can't download "delta" updates,
         | but standalone OS installers/updaters can be downloaded.
         | 
         | Go to https://apps.apple.com/app/macos-big-sur/id1526878132
         | (for Big Sur), click "Get", use Software Update to monitor the
         | download progress, then "rescue" the installer ("Install macOS
         | Big Sur.app") from Applications folder.
        
       | Toutouxc wrote:
       | Does anyone have any info on why the actual macOS installation
       | isn't bootable by both architectures? I seem to have lots of
       | different universal and x86_64 binaries and kexts on my M1
       | machine.
       | 
       | Also the kernel (that I thought was the actual kernel in use) in
       | /System/Library/Kernels reports "Mach-O 64-bit executable x86_64"
       | so I'm kinda confused about all this.
       | 
       | I'd appreciate any pointers.
        
         | pram wrote:
         | I presume it's because the M1 variant doesn't use EFI to boot.
        
           | Toutouxc wrote:
           | That's what I'm expecting to learn, but I wonder what's going
           | on inside regarding the kernel and dylibs (and other stuff I
           | don't understand yet).
        
         | my123 wrote:
         | On your M1 machine, the used kernel is
         | /System/Library/Kernels/kernel.release.t8101. (for T810x
         | processors, A14 is T8101 and M1 is T8103, both share the same
         | kernel)
         | 
         | The installation should be bootable by both, but not sure that
         | the flow to bless an install done on another machine to be
         | bootable on an other M1 one is done/fully functional yet. (on
         | M1 machines, you need to bless external volumes before booting
         | from them)
         | 
         | Booting an install done on an M1 on an x86 Mac should work
         | already though.
        
           | marcan_42 wrote:
           | That's not the kernel. I mean, it's the kernel, but not the
           | kernel that the machine boots from.
           | 
           | The built-in bootloader actually boots iBoot2 from
           | /System/Volumes/Preboot/(UUID)/boot/(long
           | hash)/usr/standalone/firmware/iBoot.img4, and that then loads
           | the Darwin kernel from
           | /System/Volumes/Preboot/(UUID)/boot/(long hash)/System/Librar
           | y/Caches/com.apple.kernelcaches/kernelcache.
           | 
           | However, the system firmware can only boot this from the
           | internal SSD, not from any external storage. When you choose
           | an external disk to boot from (the "bless" thing), those
           | files get copied to the internal SSD, and it boots from that
           | instead.
        
             | comex wrote:
             | But note that Intel Macs use a similar but completely
             | different system, also redone in Big Sur, with a set of
             | "kext collection" files in a different location and format.
             | Because that makes so much sense.
        
             | mrkstu wrote:
             | So you literally cannot boot an M1 Mac with a nonfunctional
             | internal drive, even if you're successfully 'booting' from
             | an external drive before it fails? The SSD is integral to
             | its functioning?
        
               | my123 wrote:
               | Yes.
        
               | mrkstu wrote:
               | Good to know- glad I got a terabyte drive then, since it
               | will less likely suffer a wear failure in its usable
               | lifetime, but sad that a wear part guarantees a finite
               | lifetime for a machine with no moving parts.
        
             | my123 wrote:
             | That's the immutable kernelcache shipped by the machine,
             | and isn't only the kernel but also includes the kexts.
             | 
             | You can then rebuild your own kernel cache from
             | /System/Library/Extensions and /System/Library/Kernels.
             | (eventually with a recompiled kernel)
        
       | sdfhbdf wrote:
       | I don't see it in mentioned in the article but could be a driver
       | issue for the enclosures of theses disks. Had that happen when I
       | was using shitty cables for an SSD to my Raspberry.
       | 
       | Otherwise it's entirely possible it's for security reasons and
       | somehow related to the secure enclave stuff.
       | 
       | But I might way out of my depth here.
       | 
       | What is the use case for using an external boot disk with a mac?
        
         | yoz-y wrote:
         | One thing that comes to mind is that as a developer you don't
         | have to pollute your main partition with a beta if you can
         | install it on an external drive.
        
           | londons_explore wrote:
           | SSD's support namespacing allowing exactly this...
        
           | gtufano wrote:
           | AFS has containers to install betas on the same partition,
           | the main partition is not polluted (and the additional
           | volume(s) can be removed at will). cfr.
           | https://support.apple.com/en-us/HT208891
           | 
           | I'm not saying that it's "normal" not to be able to boot from
           | external devices, I'm just answering your point
        
             | minimaul wrote:
             | This is quite risky - previous beta updates (such as Big
             | Sur) did break installing updates on older OS releases in
             | the same APFS container, and some beta updates have in the
             | past done incompatible APFS updates that broke the ability
             | to boot old OSes.
             | 
             | Safer to use a separate disk or partition.
        
         | londons_explore wrote:
         | The fact the errors occur before the "reboot" part of the
         | installation tells me it isn't a driver issue. The "unable to
         | set startup disk, SDErrorDomain 104" suggests the error is a
         | check in firmware preventing this.
         | 
         | It's probably simply unimplemented, and rather than try anyway
         | there is a check somewhere in the firmware that the drive being
         | marked bootable meets some criteria. Clearly the internal drive
         | meets that, and _some_ external drives do. Running a tracer on
         | the commands sent to the drive would likely identify it.
        
         | LocalH wrote:
         | I don't even think it should have to be justified. Booting from
         | external media is one of the most basic computer maintenance
         | tools we have. It's not like the computing industry has been
         | giving two shits about user freedom anyway. The cynic in me
         | wants to say that the insecurity of modern computing was
         | intentional, so as to eventually require such user-hostile
         | lockdowns. However, the rationalist in me understands that it
         | most likely just ended up happening this way by chance. Either
         | way, it's unfortunate that everything is being locked down more
         | and more in the name of security. At the very least, such
         | walled gardens should be _opt out_.
        
           | [deleted]
        
         | jlokier wrote:
         | - Booting to recover your data when the system has trashed
         | itself, typically due to a failed software update, to the point
         | that it won't boot off the internal drive but the drive is
         | still working. This sort of thing has been seen with older MBs.
         | 
         | - Continuing to be able to use your laptop when the internal
         | drive has failed. Very helpful if you can't afford a
         | replacement, or if you need to carry on without waiting for a
         | replacement and you have a recent backup.
         | 
         | - Booting older versions of MacOS (that don't know about APFS,
         | or if you have reason not to trust APFS partitioning) for
         | testing, compiling for an older target, running software that
         | doesn't run on the current version of MacOS, or other reasons.
         | 
         | (But old MacOS won't work with the M1 so that doesn't matter at
         | the moment.)
        
         | simonh wrote:
         | * Recovery of the machine from an external clone disk in case
         | of disk failure.
         | 
         | * Booing up a disk from another machine where it's suffered a
         | non-disk failure.
         | 
         | * Because I want to.
        
           | shawnz wrote:
           | You could use internet recovery mode for the first use cases.
        
             | simonh wrote:
             | That will boot the OS, but not with a copy of your files
             | from the dead disk.
        
           | LocalH wrote:
           | The last reason you listed is probably the most important, as
           | well.
        
         | parsimo2010 wrote:
         | I once worked with a team that worked three 8 hour shifts and
         | flexible seating, so there were about 3 times as many workers
         | as there were desks and each team member might be sitting at
         | several possible computers. Rather than worry about syncing
         | personal files and profiles across a network, each team member
         | had their own external drive that they used to boot the Mac
         | mini wherever they were sitting. There may have been better
         | solutions for that particular team, but this certainly worked
         | and I'd hate to throw away the option for doing something like
         | that in the future.
         | 
         | And I've booted Linux from an external drive a zillion times on
         | a PC. It's fairly handy to have the option.
        
           | londons_explore wrote:
           | Performance kinda sucks unless you pay a lot of attention to
           | buying the right model of drive. Most drives are simply
           | designed for storing a few TB's of photos and videos. As soon
           | as you are doing low latency paging to the drive and millions
           | of flush() operations, things bog down pretty badly, even on
           | a modern SSD.
           | 
           | Simple things like USB not having any decent way to do shared
           | memory with the host are a big part of it...
        
           | Spooky23 wrote:
           | That's really cool.
           | 
           | I used to support a similar need with an enterprise tool that
           | cost exponentially more to implement and support.
        
       | aloer wrote:
       | OT: one of the nice little things with MacBooks is that you have
       | a disk cloning thing built in. It takes literally one step and
       | half an hour to clone my internal 512gb ssd to external Samsung
       | t5 and have it booted up. No problems whatsoever and I've been
       | successfully copying the same system back and forth about 10
       | times last year
       | 
       | One thing I do recommend though: remove airpods from the Apple
       | account before cloning and pair again once the same system is
       | running on new hardware. Sometimes this causes problems
        
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