I was recently handed an old backup hard drive that my co-workers couldn't read because it used one of the EXT file systems. They didn't tell me what they wanted at first, so I assumed I should try to get the data off of it.
I ignored it, because I knew I would need to install
ext4fuse, which I did, and I was able to read the disk just fine. Only after that, my coworker told me that he wanted the disk erased and formatted with a filesystem that he could use on his PC. But even though I had the disk mounted and readable, my attempts to format it failed. I tried:
- Disk Utility > Erase > ExFAT, which gave a simple "operation failed" error,
diskutil eraseVolume ExFAT NewName disk2, which gave a "cannot unmount disk" error,
umount, which gave a "disk isn't mounted" error, and
- all of the above after unplugging the drive various ways.
Finally, I rebooted, and when I plugged in the drive again, I was asked to initialize, eject, or ignore. I choose to initialize this time, and suddenly I could erase to various formats with no issues.
This behavior surprised me because I assumed "initialize*, erase, and format were all synonyms. I guess they're not. So what's the difference? How can one force the initialize dialog to appear?