Disk Utility acting weird

Every once in a while I will see something odd like this with Disk Utility where there appears to be a phantom device/Container, although I've never seen it quite like this before. It can be tricky to get rid of because some of those items will not allow you to interact with them.

Since this is an external drive, try rebooting the Mac to see if things improve. If you still have the same issue, then try deleting the APFS "Data" volume which may trigger Disk Utility to ask if you want to delete the Container (or maybe all of the APFS volumes within the Container). With later versions of macOS, this needs to be done before Disk Utility will allow you to select the physical drive to erase which in this case is the "WD Elements 25A2 Media" item. It is hard to say which item or items you will need to delete, but deleting is the first thing that must be done here. I've only seen this a couple of times over the last couple of years, so I don't recall which item is the one you need to deal with here as I just remember the basic procedure.

If you cannot delete any of these APFS volumes or Containers on either of these "twin" sets, then you will need to use the command line instead to write zeroes to the beginning of the drive to destroy the partition table. This can be risky so make sure to disconnect all other drives first to minimize the chances of a mistake being made and losing data on another device.

You will need the current drive identifier for the WD drive which you can get from Disk Utility, or you can get it by using this command in the Terminal app (I'm assuming the WD drive will be the only external drive connected -- keep in mind some external devices may also appear as a "drive" so it is best to disconnect all other external devices just to be safe and make things easier). Keep in mind the drive identifier may change each time you eject & reconnect a drive or reboot, so make sure to always get the current drive identifier.

With all of the following command I will be using "diskX" in the commands as a placeholder. Make sure to replace "diskX" with the correct drive identifier for your drive.

diskutil  list  external  physical

Unmount all volumes on the physical drive ("diskX"):

diskutil  unmountDisk  diskX

Now write zeroes to the beginning of the drive identified as "diskX":

sudo  dd  if=/dev/zero  of=/dev/diskX  bs=100m  count=10

This command will prompt you for your admin password. Nothing will appear on the screen as you type the password. Press the "Return" key to submit the password.

If there are no errors reported, then you should be able to use Disk Utility as normal to properly erase the physical WD drive.

tiagorocha wrote:

I can't even really explain this whole thing, but I will try:

I have this disk that had 3 volumes. It was behaving weird and decided to just erase everything and start fresh.

Now sometimes I create a single partition, it creates it, but it shows me an old volume that I can't mount, but then creates something separate saying Container 5, with a volume with the name I chose when I created the partition.

Sometimes it creates the partition, I can't see it inside Disk Utility, but then I see it on Finder.

I tried both the partition and Erase, but it never completely wipes everything so I can start fresh. it seems that it keeps some sort of "log" and keeps adding old volumes...

I tried both APFS and MacJournaled, but I never get a good result.

Again, it's hard to explain it, because it seems to always behave different every time I try to partition or erase.

Anyone knows what could cause this kind of behavior? Is there a way to completely delete everything as if the disk is brand new?

I used Erase on the main disk (the one with the name of the brand like "WD Elements 25A2 Media", as APFS (even though it shows me that's being formatted as Journaled) and I get this:

https://discussions.apple.com/content/attachment/9f3b6339-ddc9-49c1-8169-3391f65fd977

The Container disk5 and Untitled is created, but the D3 - Secondary, which is the old volume, is not deleted.

Using the Partition option, as APFS, I get the same results.

If I choose Erase and then Journaled instead of APFS, I get this, where it doesn't even show up inside Disk Utility, but I can see it in Finder (left is Disk Utility, right is finder's sidebar):

https://discussions.apple.com/content/attachment/6ebf507b-83f8-4e1d-b0bc-14c73ab83eb8

You can erase/reformat/initilze the drive as new and compare your results moving forward. This will of course delete all data.

This would be the parent drive, not the Container level, not the Volume level

DiskUtility>Show All Device, the Parent drive is the top most

Erase and reformat a storage device in Disk Utility on Mac

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

3-2-1 Backup Strategy: three copies of your data, two different methods, and one offsite. More than one device, more than one backup methodology.