I am doing a fresh install of macos Big Sur on a 16" MacBook Pro and I have managed to

  • backup all files I need
  • create a Big Sur install media
  • boot from this USB drive (Disabling Secure Boot, enabling boot from external drive)

Now I am running Disk Utility and I am presented with the following state

  1. Internal (this is my internal SSD drive)
    • Macintosh HD (this is an APFS volume)
    • Macintosh HD - Data (this is an APFS volume)
  2. External (this is the install media I created)
    • Install macOS Big Sur
  3. Disk Images (Not sure what this is)
    • macOS Base System

In the past I just erased Macintosh HD (the only internal drive) and would install the OS on it. Everything from OS data and user data would be gone that way. Now I want to achieve the same but Iam unsure if I should erase both or if maybe one contains OS stuff I should not erase. Is this structure/naming even required?

What should I do to have an absolute clean install OS, without bricking my machine?

  • I define the old as using the Disk Utility to erase the internal drive and then create a single Mac OS Extended (Journaled) volume using a GUID Partition Map. If you did this, then you would be OK. The Big Sur installer would automatically convert to APFS. Mar 23, 2021 at 2:36


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