I plugged in the T7 bShield into my M2 MacBook Air running Sonoma. I am going to use it as a back up drive with Super-Duper. Do I rename it before it is formatted?
I went to Disk Utility to format it. (T7 is EXFAT now). Then I thought the next step would be to Erase and choose a Mac format — I thought it would be APFS, but that wasn’t a choice! (see screenshot.)
No APFS.
The choices are
MAC OS Extended (Journaled),
Mac OS Extended ( Case-sensitive, Journaled)
MS-DOS Fat
I am at a loss of what to do next! Please give me explicit directions — I need all the help from you. (I am SO glad Tidbits has so many people who know what they are doing!)
It’s because the partition map is ExFAT (see the text under ‘T7 Shield’ in the main part of the window), and presumably this PC-based partition type doesn’t support the APFS format. Instead of just choosing Erase, you need to choose the Partition option in disk utility and choose to use the ‘GUID Partition Map’ type. This will allow you to format as APFS (as well as Mac OS Extended).
As @jzw wrote, this is because APFS volumes can only be created on a device that uses the GUID partition type.
Here are two tips that should help quite a bit.
As shipped by Apple, Disk Utility only shows storage volumes. Not devices. This means there isn’t an easy way to add/remove/resize partitions or to change the partitioning scheme.
Because of this, I recommend that you tell Disk Utility to show all devices. You can do this from the View menu (see the red-circled menu item below). Once you change this, it should stick, so you won’t need to do this again unless you change it back to showing only volumes:
In this view, you will see the hierarchy of devices, to containers to volumes and even some snapshots.
When you want to erase an entire device (not just one volume), select the device (e.g. the line I circled in green in the above picture). If you erase that, you will see a different confirmation dialog allowing you to specify the disk partition scheme:
This is the scheme used by Macs prior to Mac OS X 10.4.
It also can not support devices larger than 2TB.
It is the only partition type recognized by old versions of Mac OS (10.3 and older).
Unless you think you will be using the device on a very old computer, there’s no reason to not use a GPT partition table.
So why don’t devices come factory-initialized with GPT? Because they want to be compatible with all computers (even really old ones) out of the box. Every operating system used today can recognize an MBR-type partition table. So unless the device is larger than 2TB, they typically come pre-partitioned with an MBR partition table.
But it does mean that you will have to change the device’s partition table scheme in order to create APFS volumes.
I did NOT get the result you did! I clicked on Devices and it shows Samsung PSS….( I didn’t expand the … ) and under that icon for T7 Shield, I clicked on the T7 . For Mount Point it says /Volumes/T7 Shield.
My choices are; Volume (grayed out) , First Aid, Partition (grayed out) Erase Restore Unmount.
I expanded the PSS… and it says Samsung PSSD T7 Shield Media.
Should I have chosen Samsung PSS … that and not the T7 icon?
The Samsung PSSD choices are Volume (grayed out); First Aid; Partition (grayed out); Erase; Restore; Mount (grayed out)
