Is there any reason to try to have a bootable clone for backup purposes these days? Or if the internal SSD fails, is the computer likely to be unbootable anyway? Drives are backed up with 3-2-1 redundancy, but it's the first time in forever that I couldn't boot off of one.
The state of bootable clones on M1 Macs
- Thread starter leet
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Have you looked into the architecture?
It's pretty complex now and breaks a lot of the implicit assumptions made when imagining e.g. a Windows XP installation. There is a single drive containing most of the data with a single GPT map and a single APFS partition (at least to start), but then there are several volumes each with their own "role", and the "system" as most people think of it is a volume group of the System and Data volumes merged together at runtime.
With macOS Big Sur the System volume is cryptographically signed so it has a fixed layout, and in fact macOS boots from an APFS snapshot (an upgrade from Catalina mounting it read-only).
Target Disk Mode has been replaced with Mac Sharing Mode, which is network-based and shares files over SMB (asr(8) and other block-based solutions are unavailable).
The internal drive is encrypted at rest (even if you don't enable FileVault2), so it can't be separated from the Secure Enclave anyway. recoveryOS is something else altogether.
In addition to the main SSD there are other firmware devices with their own NVRAM.
I'd say the best bet is encrypted Time Machine backups, which now use APFS themselves so they're a lot more stable than they used to be, but even they're not what you might call "bootable". If you have to restore an M1 Mac using Apple Configurator 2, there are basically two options: restore, and revive.
It's pretty complex now and breaks a lot of the implicit assumptions made when imagining e.g. a Windows XP installation. There is a single drive containing most of the data with a single GPT map and a single APFS partition (at least to start), but then there are several volumes each with their own "role", and the "system" as most people think of it is a volume group of the System and Data volumes merged together at runtime.
With macOS Big Sur the System volume is cryptographically signed so it has a fixed layout, and in fact macOS boots from an APFS snapshot (an upgrade from Catalina mounting it read-only).
Target Disk Mode has been replaced with Mac Sharing Mode, which is network-based and shares files over SMB (asr(8) and other block-based solutions are unavailable).
The internal drive is encrypted at rest (even if you don't enable FileVault2), so it can't be separated from the Secure Enclave anyway. recoveryOS is something else altogether.
In addition to the main SSD there are other firmware devices with their own NVRAM.
I'd say the best bet is encrypted Time Machine backups, which now use APFS themselves so they're a lot more stable than they used to be, but even they're not what you might call "bootable". If you have to restore an M1 Mac using Apple Configurator 2, there are basically two options: restore, and revive.
I’ve read some of the articles on Eclectic Light Company, probably mostly before I got my Mini when the issues were mostly irrelevant to me. I do understand it’s a PIA, thus my question. For backup purposes (as opposed to booting different OS versions, say), is there any point, and is it worth the hassle?
For myself I'd say it doesn't make sense. It would be like trying to access the NAND in an iPhone and trying to reimage that. Most people don't have the expectation that it would be a good idea.
It may be possible in a single version of macOS to work out all the technical issues and find workarounds to actually write every block of the main storage again from a previous image, but as all the documentation above shows, it's not a simple thing.
Imagine thinking you got it all right then it trips up when restoring because one little thing was wrong or missing? I don't think anyone wants that in a "safety net" solution.
I've been a long-term Time Machine user and really appreciate that they've kept it going and improved it technologically. Now that the system isn't backed up and it uses APFS snapshots it's much better. I like knowing that my backup solution is fully supported for when I need it.
It may be possible in a single version of macOS to work out all the technical issues and find workarounds to actually write every block of the main storage again from a previous image, but as all the documentation above shows, it's not a simple thing.
Imagine thinking you got it all right then it trips up when restoring because one little thing was wrong or missing? I don't think anyone wants that in a "safety net" solution.
I've been a long-term Time Machine user and really appreciate that they've kept it going and improved it technologically. Now that the system isn't backed up and it uses APFS snapshots it's much better. I like knowing that my backup solution is fully supported for when I need it.
I run Monterey on an intel 2014 vintage Mac Mini and a new 14" MacBook M1 Pro. In both cases, I run backups using Carbon Copy Cloner. Based on the best advice I can glean from CCC developer, I no longer create a bootable external backup.
As others have suggested, a fully bootable clone is probably more work than it's worth at this point. I still use CCC to create a non-booting clone as part of my overall backup system/method, but I lean on the fact that Apple has made it easier and more straight forward to re-install a working system image. I'd rather focus on protecting my data through the usual multi-layered approach.
Use Time Machine, by all means. I use it. But rely on it? No way. I've had Time Machine vomit all over everything more times than I can count. It's the most fundamentally unreliable backup method I've ever used on a Mac (YMMV).
Use Time Machine, by all means. I use it. But rely on it? No way. I've had Time Machine vomit all over everything more times than I can count. It's the most fundamentally unreliable backup method I've ever used on a Mac (YMMV).
Agreed. The need for a bootable backup has kind of been negated by the move to a more immutable system image that is so easy to restore directly from Apple. With modern Mac OS, what is much more important is restoring your personal data; system data, Apple has you covered.
100% agreed. "Fully supported" doesn't mean it's not unreliable as hell and janky up the wazoo. Butterfly keyboards were "fully supported" too, but they were incredibly unreliable. Time Machine is "fully supported", but unlike with a Butterfly keyboard, will Apple give you any compensation or pay for file recovery services if you lose an important file because Time Machine barfed? So I don't really understand what advantage "fully supported" is supposed to confer on Time Machine.
The #1 thing you need from a backup solution is reliability, and Time Machine just can't provide that. If Time Machine was shit in the past but Apple swears up and down that it's fixed now, I don't want to be the guinea pig to test that with my data. Backups are one of those areas you want to go with time honored solutions that you know have worked for years.
I had my ZFS array recently warn me my data was corrupt, so I grabbed my 10 TB of backups down from Google Workspace, checked against my PAR2 files to ensure integrity, and I'm back in business. I would be hesitant to trust that Time Machine would A) warn me truthfully that there is verifiable data corruption, and B) that I would actually be able to restore my data without issue, and ensure that all 10 TB have full integrity and are not corrupt themselves.
One more thing I forgot to mention, Software Updates are now personalized on Apple Silicon, so "clones" aren't exactly transferrable to other machines as-is. Even the tools provided to IT allow downloading some of these items ahead of time, but the device still needs to connect to the internet during installation.
Thanks everyone for the replies. I intentionally left the OP a little vague (other than specifying for backup, not to run an alternate OS/OS version) to make sure I wasn't missing anything.
It feels a little weird not to have a bootable backup. I'm pretty sure I've had one since the days of my PowerMac 6100, and Zip drives. Sounds like multiple TM backups/clones/offsite backups is an appropriate system these days.
It feels a little weird not to have a bootable backup. I'm pretty sure I've had one since the days of my PowerMac 6100, and Zip drives. Sounds like multiple TM backups/clones/offsite backups is an appropriate system these days.
In the era of sealed system volumes, Time Machine makes things incredibly easy when it works—but, as others have said, it's temperamental. I've had to spend way more time than any Apple user should going through poorly documented procedures to repair backups and, for that matter, just keeping my network Time Machine server online. It should be a simple, clear, and reliable process and it is none of those things. The backups themselves seem more robust in Big Sur/Monterey with APFS, but the server piece is flakier than ever.
So I use it, but I also use Backblaze; keep most of my personal documents in iCloud Drive and my work documents in my work OneDrive; and make separate copies of certain critical files onto another physically separate disk manually.
With that said, I've done a couple of restores from Time Machine that appear to me to be flawless, so it can be a helpful first layer in a multi-layer strategy.
So I use it, but I also use Backblaze; keep most of my personal documents in iCloud Drive and my work documents in my work OneDrive; and make separate copies of certain critical files onto another physically separate disk manually.
With that said, I've done a couple of restores from Time Machine that appear to me to be flawless, so it can be a helpful first layer in a multi-layer strategy.
I imagine you'd get a lot more consistent TM experience with a directly connected drive dedicated to it. I use one of my 4TBs for my 512GB internal and just let it fill as much as it wants. Been rock solid for as long as I can remember. I also use BackBlaze to back up the other pair of 4TB bulk storage drives, as well as the 1TB pocket drive Music folder clone (I manually fire off an Apple Script every few days to sync that one).
Agreed. Apple doesn't sell hardware any more that is designed to work as a network Time Machine server, so while the software functionality still exists, it's very fragile. I would trust an HDD Time Machine more.... but that's still not very much. I haven't tried Time Machine since APFS, but I'll give it a few more years to build a reputation before I fully trust it again.
One of the feature holes of Time Machine is that there is no real way to verify restores. A restore is kind of useless unless you can guarantee everything is back to the way it was before the failure. Furthermore, you can't prospectively verify a backup unless it's a network backup, and then, the verification mechanism is very opaque. What does it actually do to verify? Who knows. ¯\_(ツ)_/¯
https://support.apple.com/en-ca/guide/m ... h26840/mac
This is one of the reasons I don't feel that Time Machine is serious backup software. Better than nothing, maybe? But not that great.
I'm sure that's right, but it also seems, well, really weird. The overwhelming majority of Apple computers sold are laptops. People are not sitting in one place with their laptops such that they can always be hooked up to spinning rust on a desk. For me, at least, the vision of TM is far more compelling when it's backing up everybody's computer in the house while people just use them normally than when it only backs up when you actively connect a particular drive.
But Apple never cares about all the things we want it to care about.
Which is why the discontinuation of the TimeCapsule never made much sense to me, Sure I would never ONLY rely on TimeMachine but it worked great for the occasional file restore
Sanity. Assurance of bitwise perfection.
Is it though?
A few commands..
no. It copies most of the files best effort with silent fail like TM
Describe array config.
How is this not simple for bootable bitewise clones?
apple discussion end of URL: DOC-250005828
How To Clone Your Mac Using ASR
steps by Encryptor5000necro'd to save other people needless frustration