Can you install High Sierra and not convert to APFS?

Eagle36

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Original poster
Jul 22, 2016
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I understand the GM code for High Sierra 10.13 APFS does not support fusion drives, but can you install High Sierra without APFS?
 
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caramelpolice

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Oct 6, 2012
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If you have a completely SSD-based Mac, you get converted to APFS. If you have a hard drive or Fusion Drive, you stay on HFS+. There's no options not to convert an SSD Mac, or to convert a HDD/Fusion Mac.
 

Eagle36

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Original poster
Jul 22, 2016
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I guess APFS is required for some of the features/function of High Sierra.
 

joshfairweather

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Sep 15, 2017
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Apple's website does actually specify that it will work on HDD but isn't automatically converted. It is simply optimised for SSD. Does that mean HDD users lose some new features along with other obvious benefits - possibly. @dosdude1 will be able to correct me if I'm wrong but from what I gather, you can upgrade to HS, then use disk utility to convert your HDD to APFS and keep your data, reverting back to HFS+ will cause you to lose your data.

Also, if you do update to APFS on a HDD on an unsupported mac, your computer will boot in verbose mode where you will see a black screen with all the boot commands and processes running in white text.
[doublepost=1505862866][/doublepost]@dosdude1 whilst we are on the topic, come Monday 25th on official release date, will the download link on your website provide a full final release version of HS or will it be a few days till that is up?
 

dosdude1

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Feb 16, 2012
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Apple's website does actually specify that it will work on HDD but isn't automatically converted. It is simply optimised for SSD. Does that mean HDD users lose some new features along with other obvious benefits - possibly. @dosdude1 will be able to correct me if I'm wrong but from what I gather, you can upgrade to HS, then use disk utility to convert your HDD to APFS and keep your data, reverting back to HFS+ will cause you to lose your data.

Also, if you do update to APFS on a HDD on an unsupported mac, your computer will boot in verbose mode where you will see a black screen with all the boot commands and processes running in white text.
[doublepost=1505862866][/doublepost]@dosdude1 whilst we are on the topic, come Monday 25th on official release date, will the download link on your website provide a full final release version of HS or will it be a few days till that is up?
It is not recommended that you use APFS on an HDD or fusion drive. You can install to an HFS+ partition, and are able to convert it later to APFS using Disk Utility. That only works, though, if installing from a USB drive. If you're installing by running the installer app from within another install of macOS (on a supported machine, of course), it will automatically convert your machine to APFS if it has an SSD. To download the full release when it comes out, you can use the App Store on a supported machine, or the built-in downloading feature of my macOS High Sierra Patcher tool if you're using an unsupported machine.
 

Fishrrman

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Feb 20, 2009
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Here is how I think it's possible to "work around" force-conversion to APFS when installing HiSierra onto an internal SSD.

NOTE: This requires that you also have either an external platter-based hard drive, or perhaps a USB flash drive of sufficient capacity to "hold the install".

Actually, I think a second flash drive will be needed, as well.

You'll also need either CarbonCopyCloner or SuperDuper.

The following process might work only on Macs that DID NOT SHIP with HiSierra as the initial OS.

Have the HiSierra installer in your applications folder, and then create a bootable copy of the installer on a USB flashdrive.

Boot from the flashdrive installer.

Install a clean copy of HiSierra onto the platter-based hard drive.

When done, do a brief initial setup, but DO NOT "sign into" Apple. All you want to do is create a temporary account so that HiSierra is bootable from the hard drive.

Now, put CCC or SD on the hard drive with Hi Sierra.

NOTE: I'm not sure if the version of Disk Utility that will ship with the final release of HiSierra will re-initialize the internal SSD of a Mac to HFS+ with journaling enabled. We're going to have to await the public release to know this.
IF it cannot, you will need ANOTHER bootable external drive that has a copy of Sierra, El Capitan, etc., -- that CAN initialize the Mac's internal drive to HFS+ with journaling enabled.

Now, use CCC (or SD) to clone the contents of the [hard drive] HiSierra install to the internal SSD.

When done, power down, remove all external drives, and try rebooting the target Mac and see if HiSierra boots up under HFS+ on the internal SSD.

I've got a hunch that this will work.
I don't have any idea yet as to how such a configuration will work with regular Mac OS updates afterwards.
But again, my "workaround" with system software updates would be to update the external platter-based hard drive, then re-clone as necessary to the internal SSD.
Clunky, but it might work...
 

Eagle36

macrumors member
Original poster
Jul 22, 2016
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After additional research it does appear you will be able to install High Sierra on a fusion drive that has HFS+ filesystem.
The issue for some of the beta users is it seems the HFS+ filesystem was covered to APFS, so if this is the case you need to fall back to a HFS+ fusion configuration prior to High Sierra install. Apple most likely will supply APFS support for Fusion drives with future updates.

Take a look at this article..

https://3tech.org/2017/06/14/apfs-macos-high-sierra/
 
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Crash0veride

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Oct 10, 2016
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Cincinnati
"/Applications/Install\ macOS\ High\ Sierra\ Beta.app/Contents/Resources/startosinstall --volume /Volumes/Target --converttoapfs NO"

Should work in terminal.Maybe not. Probably have to change the file path if the installer name has changed. Worked in older betas, but you could check "/Applications/Install\ macOS\ High\ Sierra\ Beta.app/Contents/Resources/startosinstall --usage" and see if the --converttoapfs option is still there.

Edit:

Terminal command for install without upgrade for the final installer:
Code:
/Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/startosinstall --converttoapfs NO
Agree to the License Agreement and a reboot should start.
 
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br0adband

macrumors 6502a
Aug 29, 2006
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That option for --converttoapfs is there in the High Sierra public beta but even with that command line it's not actually working for whatever reason, at least not in my testing.

EDIT:
Just attempted it again and the command doesn't seem to do anything on the first execution other than show the available options, so I did what any good computer user does: tap cursor up and send it again and voila, it worked, installing now so I'll report back on whether or not the results are positive and without APFS forced on my testing installation.

EDIT2:
And it worked, which is somewhat amazing I suppose, and HPFS+ was kept intact with no issues at all that I can currently see. Will do more testing but I'm not expecting any problems to crop up at this point.
 
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Fishrrman

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Feb 20, 2009
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br0adband wrote:
"And it worked, which is somewhat amazing I suppose, and HPFS+ was kept intact with no issues at all that I can currently see. Will do more testing but I'm not expecting any problems to crop up at this point."

That's good to hear, but...

When you have the time, could you give us an easy-to-follow, step-by-step description of exactly what you did?

A "guide" for others to follow?

It would be appreciated.
 

br0adband

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Aug 29, 2006
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I had Sierra installed, I grabbed the High Sierra public beta installer .app (go to beta.apple.com, get the feedback assistant, etc, that allows access to the download from the App Store), wait for the download to finish, when the installer executes automagically close it, open Terminal and execute the command (which I had to do twice and make sure you do have it correct with the --converttoapfs NO exactly as written), that's basically it.
 

Eagle36

macrumors member
Original poster
Jul 22, 2016
62
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So, the following screen shot for installer does not have the option to upgrade to APFS or not on later betas.. It sure would make since and easier for the GM code to have that option.

If I install use the method from br0adband posts, will that be considered by apple to be a supported install?
 

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br0adband

macrumors 6502a
Aug 29, 2006
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I can't see why it wouldn't be considering the command line option (--converttoapfs NO) is part of the installer itself, and Apple does offer the info at their support site as well.

It's not some funky hack or anything: the command supports installing the OS without the conversion to APFS, but of course it's not easy to get to and most folks won't even consider it during their upgrades when High Sierra is finalized in a few days and released. I doubt the overwhelming majority of macOS users will even notice, but those of us that do obviously have discovered a solution to NOT convert/upgrade to APFS in the process because of that command line option discovery.

That's not to say that in the next few days Apple doesn't decide to remove that option entirely but we won't know that until High Sierra is done and released, obviously. I honestly wouldn't put it past them considering some of the sneaky crap they've done over the years. :D

As for it being a method I posted, I'm just stating my experience using the command line option already presented earlier in this thread

As for it being a method I posted, I'm just stating my experience using the command line option already presented earlier in this thread Crash0veride in post #9 above.
 

Fishrrman

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Feb 20, 2009
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br0adband wrote:
"when the installer executes automagically close it, open Terminal and execute the command (which I had to do twice and make sure you do have it correct with the --converttoapfs NO exactly as written), that's basically it."

OK, so after you use Terminal to execute the "converttoapfs NO" command, just what do you next?

Close terminal (I would assume this)?
Then... launch the installer?
Any other indications once the installer is running?

I'm looking to find the correct routine to use when installing from an installer on a bootable USB flashdrive.

So far, it looks like this:

1. Boot from USB installer
2. Open Terminal
3. Enter command:
/Applications/Install\ macOS\ High\ Sierra\ Beta.app/Contents/Resources/startosinstall --volume /Volumes/Target --converttoapfs NO
(I'm guessing that some elements will have to be changed when installing to an internal volume, not sure which ones, however)
4. Enter command SECOND TIME
5. Quit terminal ?????
6. Launch installer and aim it at internal drive ?????
7. Next... ?????
 

br0adband

macrumors 6502a
Aug 29, 2006
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This method of installing based on the Terminal command only works for an upgrade install of High Sierra on top of whatever you already have (assuming it's not High Sierra). There's no reason to make a USB installer stick if you're doing an upgrade since the installer.app file is already there on the storage (hard drive or SSD or whatever) after you download it.

If you're attempting to do an upgrade or even a pure clean install of High Sierra using a USB stick then what you'd do is run Disk Utility during the initial install (don't just jump right in and keep clicking Next Next Next or you'll end up with APFS. This is for the beta so far, I can assume that the instructions will remain the same once High Sierra is officially publicly released in a few days but I cannot guarantee it will be identical, obviously this thread will have more info in a few days on that aspect - I'm still trying to make the installer.app into a bootable ISO personally but that's another thread entirely (literally).

If you want to do a clean install of High Sierra you'd boot from the USB installer stick (assuming you make one) then at the first screen of options run Disk Utility, change the View to "All Devices" and find the hard drive or the SSD or whatever and erase/partition it as MacOS Extended Journaled aka HPFS+ and then when that's done that'll be your installation target - I think the installer might change again for the final release but I can't say that for sure. I'm somewhat positive Apple is doing everything they can to hide any way of setting up the drive/partition as HPFS+ to push people into using APFS so, as long as you go step-by-step and doing everything very slowly with great care you can get it done and have HPFS+ as the file system.

But I ain't guaranteeing success with the USB installer stick method, my experience right now is strictly with the upgrade so far since I can't boot a VM with a USB installer stick (yet) and I haven't had any success making the bootable ISO.

So, again, the Terminal command mentioned above by Crash0veride applies to executing the installer.app when it resides in the Applications directory which is where it is downloaded from the App Store, either the release when it's available or the last public beta which is available now. It won't be relevant to doing anything from a USB installer stick for a clean or even an upgrade installation.

Hope that clarifies this a bit.
 

hideous cheese

macrumors regular
Feb 8, 2012
145
25
Can I convert external HDDs?
This is unclear in the Apple guidance - it says only HDD will not be converted which seemed to leave open the question of whether they could be converted at user request. I asked this on another Apple Forum and the view was that at this time no APFS option will be available at all for HDD.

fwiw, I just bought an external SSD for the purpose of using it as a boot drive for High Sierra and gradually move to that as my default. I will retain a Sierra bootable.
 

pbels

macrumors newbie
May 28, 2011
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0
Yes, after High Sierra install open diskutility, right click the external drive and click "Convert to APFS" (only works on HFS+ partitions). Now whether converting HDDs is useful is a whole other topic of discussion.

If I install High Sierra on my Rmbp and my colleagues using fusion drive disks do not, should I expect issues with file sharing internal documents
 

simonsi

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Jan 3, 2014
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Auckland
I'm confused: My normal upgrade path on my dual-SSD cMBP is to CCC the SSD boot drive to an external HDD, upgrade the HDD, once all ok CCC the HDD onto the SSD boot drive.

In this scenario the SSD will end up still on HFS+ (as will the HDD)??? HS won't convert the HDD and CCC will clones the files but not change the filesystem - do I have that right?

Can/should I convert the SSD to APFS afterwards???
 

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