Can't format drive as APFS

You might try formatting to HFS+ and then from Disk Utility's Edit menu select Convert to APFS...

Joe Redifer wrote:

I have a mechanical Western Digital Gold 12TB drive that I'd like in APFS due to the format's increased responsiveness when browsing in the Finder compared to HFS+. However every time I try to format it as such, it almost finishes, but then it fails with the following:

Mounting disk

Creating a new empty APFS Container

Unmounting Volumes

Switching disk6s2 to APFS

Creating APFS Container

tx_flush:1201: rdisk6s2 xid 1 sync/barrier failed: 5

nx_format:425: failed to finish first transaction: 5 - Input/output error

tx_mgr_free_tx:197: rdisk6s2 Trash unfinished pending tx, xid range = 0x1 - 0x1

newfs_apfs: unable to format /dev/disk6s2: Input/output error

An internal error has occurred. : (-69626)

Operation failed…

I am using GUID. I can reformat into HFS+ and it's fine. Are some drives physically just not able to exist as APFS?

DiskUtility>View>Show All Devices

you are formatting the Parent drive (top most) as GUID/APFS

ref: Erase and reformat a storage device in Disk Utility on Mac

Erase and reformat a storage device in Disk Utility on Mac - Apple Support

Volumes share space within a Container with no penalty.

ref: Add, delete, or erase APFS volumes in Disk Utility on Mac

I thought it likely to fail since the failure references an internal error, but hey, it was worth a shot.

And though an internal drive error is indicated, still you might try using a different port on the Mac and also a different cable if you have one available if for no other reason than to be thorough.

Joe Redifer wrote:

I have a mechanical Western Digital Gold 12TB drive that I'd like in APFS due to the format's increased responsiveness when browsing in the Finder compared to HFS+.

How did you come to that conclusion? Mechanical spinning HDDs should be faster formatted as HFS+. As APFS they tend to get slower and slower, especially as boot drives.

You're welcome.

So often it's the little things.

I'm happy to know that you've got it sorted. 🙂