Mac Drive Formatting Errors

[Rick Cornish]

Hey gang......
I have been consistently having trouble formatting USB hard drives. I'm running High Sierra and using Disk Utility>>Erase>>Mac OS Extended (Journaled)>>no exotic characters in the disk name.

The operation fails the first time, leaving me with a greyed-out drive with a random hex name in Disk Utility, but not visible on the desktop. When I repeat the same operation for the greyed-out disk, it works fine.

What am I doing wrong?

[mikehalloran]

Disk Utility works differently in High Sierra. It defaults to APFS.

Are you formatting an HDD or SSD?

Are you booting from APFS or HFS+, SSD or HDD?

[Rick Cornish]

Hi Mike.....
I knew you’d have some thoughts on this.

Disk Utility works differently in High Sierra. It defaults to APFS.

I didn’t know what this is until I just Googled it. Not sure I understand the ramifications, unless—by optimizing the OS for SDDs, it no longer works as well on HDDs. (?)

Are you formatting an HDD or SSD?

HDDs only

Are you booting from APFS or HFS+, SSD or HDD?

My system drive is Apple flash memory. (Does that answer your question?)

BTW: This is happening on both my late-2013 Mac Pro and my 2016 MacBook Pro (both on HS).


Sent from my iPhone using Tapatalk Pro

[mikehalloran]

Yes, it did answer the questions — thanks.

Here's the long form from Apple Support. Read the whole thing to get a better idea.
https://support.apple.com/en-us/HT208496

Format the Drive, not the volumes. Choose GUID Partition Map.

You can format HDDs as APFS in Mojave but not HDDs — which is good. As for SSDs, normally
APFS unless being used for Time machine which should be Mac OS Extended.

Never reformat a boot drive on a newer Mac running HS or Mojave to Mac OS Extended. Likewise do not partition it and run a second OS. You can spend hours trying to undo that after totally screwing up your system. I did that on an external test drive just to see ... yikes!

[Rick Cornish]

Here's the long form from Apple Support. Read the whole thing to get a better idea. https://support.apple.com/en-us/HT208496

Good article—thanks, Mike!

Format the Drive, not the volumes. Choose GUID Partition Map.

Good tip… I always wondered about this.

I'm still a little fuzzy on whether I should format disks I'm creating for project backups (not system disks, not Time Machine) as APFS or Mac OS Extended (Journaled). Thoughts?

Thanks again.