How to download macOS Sonoma installer?

Me too!

The only plausible suggestion that I've seen so far is to install Ventura on the separate volume, boot into it, and then upgrade to Sonoma. I've not tried that yet.

I don't know what use the downloadable .ipsw file is. Maybe it can be used with a virtual machine, or something?

If anyone has got Sonoma working as a dual-boot option, either on an external drive or a separate volume on the internal storage, please give us a clue how you did it!

Thanks!

@endecotp's solution is correct at this time. We haven't provided a full installer with the macOS 14 beta (23A5257q).

@endecotp Thank you for the good suggestion and @Systems Engineer thanks for the confirmation.

I was so confused if I was missing something obvious.

@Systems Engineer so what is the IPSW file for (and how to use that)? I wish there was documentation about it, all I read was it is used by Apple Configurator but that is only for iOS IPSW files.

@endecotp's solution is correct at this time. We haven't provided a full installer with the macOS 14 beta (23A5257q).

Thanks. Can you confirm that the process of installing Ventura to an external drive and upgrading that is known to work? I have seen some suggestions that there can be problems with that, but they are just "random posts on the internet"...

Is it planned to provide full installers for later betas? (What has happened in the past?)

You can use Configurator to restore IPSW images to Apple Silicon machines.

Could you use this method to restore to an external drive attached to the target machine?

I have installed macOS Sonoma on a separate volume.

1. Created a separate volume (https://support.apple.com/en-gb/HT208891).
2. Created a bootable installer for macOS Ventura using https://support.apple.com/en-gb/HT201372.
3. Install on macOS Ventura on new volume.
4. Upgraded to macOS Sonoma.

I'm failing to make this work on an external drive; I can't get it to boot Ventura from it. Is it supposed to be possible to do this?

I've tried two approaches. Firstly, I've tried to run the macOS Ventura installer and told it to install to the external drive. I then restart holding down the power button and am presented with the choice of disks to boot from, but when I choose the external drive with the new installation and click "continue", I just see a spinner for about a second and then nothing happens.

The second approach I've tried is using the createinstallmedia tool. I've partitioned the external drive using the GUID partition table with a small "Mac OS Extended" partition and a large APFS partition. I've then used createinstallmedia to put the installer on the small partition, and booted into it, which works. I then use that to install macOS onto the larger partition, which seems to work, but subsequently when I try to boot into that, I get the same behaviour as the first approach i.e. it spins for a second and then does nothing.

I note that the "Use more than one version of macOS on a Mac" page that you linked in your point 1 is specific about "a new volume of your startup disk".

I am making progress at last.

I found a clue in a post on the macrumors forum: you need to connect your external drive to a USB-A port, not a USB-C port, at least on some Macs. (Mine is an original M1 mini.)

Having done that, it installed Ventura and booted into it with no trouble at all.

It is downloading the Sonora beta as I type this. "About 1 hour remaining".

Finally working!

For the record, installing any MacOS version on an external may require updating the firmware security settings in the Restore mode. If you do an OS install but are unable to select the startup disk or booting to it fails, this might be the issue.

Additionally, getting to Restore mode (via Command-R on startup) may require detaching all other USB/TB devices before the key-combination is recognized.

In the Restore UI, the firmware security settings are not listed among the ~4 apps presented to the user, but under a menu item.

It's likely that you'll need to permit BOTH booting from externals AND relaxed verification.

Further, the OS should be installed to APFS volume. Also, in disk utility, if you get info on the install partition, it will show whether the required "System Integrity Protection" is supported. If not, recheck your firmware security settings.

It's likely that you'll need to permit BOTH booting from externals AND relaxed verification.

On my M1 Mac mini, there is no setting to enable/disable booting from external drives - I've seen the switch in screenshots elsewhere, but I don't seem to have it.

I do have the switch for "relaxed verification" but I don't believe I needed to relax it to make it work.

The lack of a macOS 14 installer is severely limiting our ability to test our applications and drivers with the new version of macOS. We do not have enough Macs to dedicate a separate test Mac for each of our test engineers just for testing macOS 14. Each new build of our products has to be tested on multiple versions of macOS; all of our products support macOS back to 10.14, some of them back to 10.12. In addition, we are completely blocked on testing on Intel Macs.

Just some feedback from outside Apple's walled garden.

Tim Standing VP Software Development Other World Computing, Inc.

I was able to use this page to get the full installer: https://mrmacintosh.com/macos-sonoma-full-installer-database-download-directly-from-apple/

Created a new APFS volume and installing to that right now.

https://mrmacintosh.com/macos-sonoma-full-installer-database-download-directly-from-apple/

You trust that site? Who owns it?

Note to Apple: you not providing a proper installer endangers developers who will end up installing potentially dangerous hacks like this one.

the links provided directly link to installer files on Apple's swcdn.apple.com website

No, it's a link to a site called "mrmacintosh".

Maybe that links or redirects or something to Apple when you visit it. Who knows what it links to when I visit it. Maybe it checks my IP address, and sends me the malware if I'm one of the victims that someone is trying to hack.

It is very unwise to use things like this - an amazingly dangerous of Apple to make it possible by apparently providing these "secret" installers.

No, it's a link to a site called "mrmacintosh".

While I agree that Apple should make it easier to get the installer, I have to stick up for the person who provided the Mr. Macintosh link. He said, "the links provided directly link to the installer files on Apple's swcdn.apple.com website." That is a true statement, I just verified. Obviously he is providing a link to a third-party website, but he is saying that the links ON that website are straight to Apple, which is true. Now, if he were suggesting that we download installers FROM that third-party website, you'd have a point.