High Sierra: Can’t merge BOOTCAMP partition with APFS container

These are two answers I got directly from Apple after emailing Tim Cook yesterday

We are clearly lacking some documentation (and probably a feature in Disk Utility). However, you can achieve the removal using Boot Camp assistant.

Launch Boot Camp Assistant Click the Continue button You should now see a “Restore Disk to a Single Partition” screen. Click Restore, enter password

Your system will now remove the windows partition.

Sorry our experience didn’t meet your expectations. I’ll work with my engineering teams and AppleCare to get this addressed.

You tube link

https://www.youtube.com/watch?v=jy7McSE_NfI https://www.macworld.com/article/1156195/mac-apps/delete-boot-camp.html

Alternatively

Getting rid of Boot Camp is super simple, you use boot camp assistant to remove what it may have created. There’s a handy YouTube video which explains this process here:

https://www.youtube.com/watch?v=jy7McSE_NfI

I’m interested in why the install failed, so before you do this if you can help us by collecting some information, great. If you don’t have time for, that’s cool too.

Using the Boot Camp Assistant to to remove the BootCamp partition:

1. Start the Boot Camp Assistant from the Utilities folder.
2. At the Boot Camp Assistant Welcome Screen click Next.
3. If the Boot Camp Assistant cannot remove the partition it will error here. If it can then you will get another dialog asking you to restore the drive (i.e. remove the Boot Camp partition).

How to create Sysdiagnose logs:

1. Launch Terminal from the Utilities folder in Applications.
2. Type: “sudo sysdiagnose” and hit the “return” button
3. Type in your password (for sudo)
4. It will prompt you to press ‘Enter’ to continue. Press the return button to continue.

Once the logs have been gathered they will be compressed into a .gz file and created in the /tmp location. A finder window will pop up also once the file is created with the correct location. We need that file as well.

Sometimes the Boot Camp Assistant fails on the first install, we are looking into this issue, if you see a failure we’ve seen reports that attempting a second install will be successful.

I have removed the Apple employee names, in line with GDPR. I hope this helps people

Spencer

There is no official documented way to add another physical storage to an existing APFS container.

I tried several possibly "undocumented" apfsVerbs like addPhysical, addPhysicalStorage or addStorage without success.

The feature may still be implemented later, since creating APFS FusionLCs is possible already:

diskutil ap createContainer [-main] device [-secondary] [device]

Example:

$ diskutil ap createContainer disk1s2 disk2s2    
Creating container with disk1s2 disk2s2
Started APFS operation on disk1s2 Data
Creating a new empty APFS Container
Unmounting Volumes
Switching disk1s2 to APFS
Switching disk2s2 to APFS
Creating APFS Container
FusionLC autodetect: LC Fusion
Created new APFS Container disk4
Disk from APFS operation: disk4
Finished APFS operation on disk1s2 Data

$ diskutil ap addVolume disk4 APFS Data
Exporting new unencrypted APFS Volume "Data" from APFS Container Reference disk4
Started APFS operation on disk4
Preparing to add APFS Volume to APFS Container disk4
Creating APFS Volume
Created new APFS Volume disk4s1
Mounting APFS Volume
Setting volume permissions
Disk from APFS operation: disk4s1
Finished APFS operation on disk4