NetInstall 10.13.4 - rotational disk converted to APFS on iMac 12,1

Number:rdar://39202183 Date Originated:05-Apr-2018 09:31 am
Status:Open Resolved:
Product:macOS + SDK Product Version:10.13.4
Classification:Other Bug Reproducible:Always
When booting to a 10.13.4 NetInstall image that has “Erase and install” enabled, on an iMac 12,1, the volume is automatically erased as expected but it is also converted to APFS.

Steps to Reproduce:
Create NetInstall set using System Image Utility, enable the “Erase and install to:” option and specify “Macintosh HD” as the target volume.

Upload NBI to NetBoot server - in our case running BSDPy and serving images over NFS.

Boot an iMac 12,1 to this NetInstall image.

Expected Results:
The target volume should be automatically erased and left as HFS+ and macOS installed

Actual Results:
The target volume is converted to APFS during installation.




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