How to delete AFS from within El Capitan?

[Eugen Mezei]

For comparison purpose I installed High Sierra onto my mid2011 iMac along with the existing El Capitan.
Reduced the Capitan partition and in the free space I installed HS. Booted into it, all smooth. But it had formatted his partition with HFS+ (thought it will go automatically to APFS). As I wanted to test APFS, I did a conversion. Rebooted, all ok.
Played around for some time with High Sierra but decided the speed is lower than with El Capitan and decided to abandon it.

Booted Capitan, no problem.
The problem is, I can not delete the APFS partition from within El Capitan and I also can not boot back into HS.
Capitan's disk utility sees the APFS partition as unknown type and can do nothing with it, not even delete it. Also tried Command+R Disk Utility, but it starts the utility of Capitan, not that of HS.

Tried the old iPartition but it says it can not delete from the boot disk. But when trying to make a boot-USBstick with iPartion on it the program crashes.

Any ideas how I escape this catch22?

 

[MarkC426]

El Capitan cannot read APFS (not AFS) file system or drives.
The earliest OS is High Sierra.

 

[MarkC426]

You may be able to install HS onto an external drive, boot from that, then modify the APFS partition.

 

[joevt]

Use iPartition.app to erase the APFS partition as HFS+? iPartition doesn't know what a APFS partition is - it is shown as a GUID. But it's just a partition so it can be removed or moved (but don't try to resize it).
https://coriolis-systems.com

 

[Eugen Mezei]

El Capitan cannot read APFS file system or drives.
The earliest OS is High Sierra.

Well... that I know.
It doesn't need to read it, just delete it. At the moment it sees an unknown type partition, but is not willing to delete it.

The other way were if I could boot HS and delete from there. That partition seems not to be active/bootable (blessed? sorry I use Windows denominations), how can I choose to boot from it? Booting into recovery helped me nothing, but possible I do something wrong.

 

[Eugen Mezei]

Use iPartition.app to erase the APFS partition as HFS+? iPartition doesn't know what a APFS partition is - it is shown as a GUID. But it's just a partition so it can be removed or moved (but don't try to resize it).
https://coriolis-systems.com

I don't understand your first sentence.

I thought iPartition would delete the APFS partition, even if I start it from an USB stick made under Capitan. But I can not make the USB stick, iPartition crashes. (Was an 8 GB stick, I try one with 4 if I find one.)

 

[chabig]

1. Boot to Recovery
2. Reformat the entire drive to 1 HFS+ partition
3. Reinstall the OS
4. Restore data from backup

 

[Eugen Mezei]

Chabig, I asked exactly for the reason that I want to avoid reformatting (and even more reinstalling OS and data).

 

[chabig]

Understood. But I think you're stuck and are going to have to either do it, or accept the loss of some space.

 

[Eugen Mezei]

I am incapable of accepting this knowing that any other OS or partition manager even if it knows nothing (can not read it) about a partition at least it can delete it. How comes this is not possible here?

 

[Nermal]

I wonder whether diskutil at the command line might be able to manage this. I'm not at my Mac right now so can't give detailed instructions, but I suspect it'll be more 'powerful' than the GUI version.

Alternatively, in a pinch you could make a 10.13 USB install drive and run its version of Disk Utility.

 

[Eugen Mezei]

Nermal, good idea. Have not thought about that.

Current partitioning:

/dev/disk0 (internal, physical): #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *1.0 TB disk0 1: EFI EFI 209.7 MB disk0s1 2: Apple_HFS El_Capitan-1011 500.0 GB disk0s2 3: Apple_Boot Recovery HD 650.0 MB disk0s3 4: 7C3457EF-0000-11AA-AA11-00306543ECAC 498.7 GB disk0s4 5: Apple_Boot Recovery HD 650.0 MB disk0s5


0s4 is the High Sierra APFS partition.
I am not sure if the two recovery partition could be of use. 0s5 must be the recovery of HS and 0s3 that of Capitan.

 

[Eugen Mezei]

Alternatively, in a pinch you could make a 10.13 USB install drive and run its version of Disk Utility.

But for that I first need access to the HS partition, or am I wrong?
L.E: Yes, I am wrong, I need only the installation media.

 

[Nermal]

Nermal, good idea. Have not thought about that.

Current partitioning:

/dev/disk0 (internal, physical): #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *1.0 TB disk0 1: EFI EFI 209.7 MB disk0s1 2: Apple_HFS El_Capitan-1011 500.0 GB disk0s2 3: Apple_Boot Recovery HD 650.0 MB disk0s3 4: 7C3457EF-0000-11AA-AA11-00306543ECAC 498.7 GB disk0s4 5: Apple_Boot Recovery HD 650.0 MB disk0s5


0s4 is the High Sierra APFS partition.
I am not sure if the two recovery partition could be of use. 0s5 must be the recovery of HS and 0s3 that of Capitan.

I found the man page for diskutil. It looks like you want "sudo diskutil eraseVolume free free disk0s4". Double-check that 0s4 is the right volume, although it looks OK from your listing.

 

[Eugen Mezei]

I found the man page for diskutil. It looks like you want "sudo diskutil eraseVolume free free disk0s4". Double-check that 0s4 is the right volume, although it looks OK from your listing.

Hope it will erase it from the EFI too.

 

[Eugen Mezei]

It worked. Partition is deleted, space is free.
Now I will install Mountain Lion. (Still trying to find out the fastest OS for my -fairly simple- use.)

Do I need to always bless the partition I want to boot at the next restart? I remember that from old MacOS versions.

 

[Nermal]

Do I need to always bless the partition I want to boot at the next restart? I remember that from old MacOS versions.

I don't think that's been necessary since OS X (I don't even know how you'd do it now).

 

[Eugen Mezei]

Oh dear... seems ML can not be installed if on the drive is already (even in a different partition) Capitan installed. Do I really have to use a bootmanager like Clover?

 

[DeltaMac]

If your hard drive now has a free space partition ---
Boot to an external ML installer.
At the menu screen, launch Disk Utility.
Format (erase) that free space, formatting as OS X Extended (Journaled)
That should only take a few seconds to complete, then quit Disk Utility, then choose Reinstall OS X.
Should let you choose that new partition this time.
To answer your question about "blessing" -- the installer will take care of that. In fact, your ML system partition will be set as the default boot drive, as a result of the install. If you want to set the default for your El Capitan system again, you can do that from the Startup Disk pref pane in System Preferences. To boot to the other system without setting as default, you can just restart holding Option, then select your chosen boot system from that Option-boot picker. (That is your boot manager for Mac systems, and some other OSes. Doesn't always show non-Apple systems, but you would be using something else for those, such as Clover, in that case. Shouldn't be needed for properly installed Apple systems...

One more note: You can install other Mac OSes on a single hard drive by adding more partitions, as long as each partition has enough space for the system install. I have an external SSD with every Mac OS from Leopard to Monterey, all on the same drive. (I like the convenience of troubleshooting with different systems, without needing to swap out external drives each time)

 

[Eugen Mezei]

just restart holding Option, then select your chosen boot system from that Option-boot picker. (That is your boot manager for Mac systems, and some other OSes.

That was what I thought when I installed High Sierra. Thought it would allow me to boot El Capitan or HS. But than I ended up with the manager of Capitan, that did know nothing about APFS.
In the future (after putting some more RAM and an SSD in the iMac) I still intend to have a triple boot system: ML, Capitan, HS. How do I force that the boot manager of HS remains always the one in command and not be replaced with one that can not handle APFS?

As for free space, I ran into the next problem.
After deleting the APFS partition diskutil had to make some repairs. Now the recovery partition extended into the full free space. Any idea how I shrink it?

/dev/disk0 (internal, physical): #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *1.0 TB disk0 1: EFI EFI 209.7 MB disk0s1 2: Apple_HFS El_Capitan-1011 500.0 GB disk0s2 3: Apple_Boot Recovery HD 499.9 GB disk0s3

 

[chrfr]

That was what I thought when I installed High Sierra. Thought it would allow me to boot El Capitan or HS. But than I ended up with the manager of Capitan, that did know nothing about APFS.
In the future (after putting some more RAM and an SSD in the iMac) I still intend to have a triple boot system: ML, Capitan, HS. How do I force that the boot manager of HS remains always the one in command and not be replaced with one that can not handle APFS?

As for free space, I ran into the next problem.
After deleting the APFS partition diskutil had to make some repairs. Now the recovery partition extended into the full free space. Any idea how I shrink it?

/dev/disk0 (internal, physical): #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *1.0 TB disk0 1: EFI EFI 209.7 MB disk0s1 2: Apple_HFS El_Capitan-1011 500.0 GB disk0s2 3: Apple_Boot Recovery HD 499.9 GB disk0s3

You really should just back up your data, erase the disk, and start over at this point.

 

[DeltaMac]

I've experimented with the various boot systems, and, in my experience, if you have multiple boot partitions on a drive, then the boot process uses the partition that belongs to whatever system is set as the default boot system. That is the version that you set as default in the Startup Disk pref pane. As you have seen, if you are booted to El Capitan, that system is too old to recognize a system that is installed on an APFS partition.
So, if you are booted to El Capitan, you can't change the boot system to High Sierra (on APFS) directly, while you are still booted to El Capitan. But, it is easy to restart, holding the Option key. You will get the firmware bootpicker screen, where you should see all of the choices that your Mac model is capable of booting. Select the High Sierra boot, and press Enter/Return to continue to boot to High Sierra. If you want to use High Sierra as the default boot, then change that selection in the Startup Disk pref pane, while you are booted to High Sierra. It's a bit of a bother, but part of the game when you have multiple boot systems available on your Mac...

 

[joevt]

then change that selection in the Startup Disk pref pane

You can change it in the boot picker by holding the control key down (the arrow under the OS icon turns into a circular arrow) and press enter. It changes the default startup item and boots it.