Delete external disc partition

[whooshbong]

I have just moved from a iMac to new Mac mini and plugged in my Thnderbolt 2 Western Digital 4tb HDD. I previously had it partitioned into two equal parts. I now want to make a 1/3TB partition and use the 1TB for Time machine and the 3tb for storage, whilst retaining information originally in one of the 2tb that will become 3.

The problem is that macOS seems to be seeing the external drive as two physical drives and won't let me undo the original partition. Any ideas?

 

[Fishrrman]

1. Open disk utiity
2. Is there a "view" menu in the menu bar?
3. If so, go there and see if there's a choice, "show all devices"
4. If it's there, choose it and start over.

 

[whooshbong]

1. Open disk utiity
2. Is there a "view" menu in the menu bar?
3. If so, go there and see if there's a choice, "show all devices"
4. If it's there, choose it and start over.

it already is

 

[Fishrrman]

Did the WD drive come with any factory-installed proprietary software?
Sometimes, this could prevent a "complete reformat" of the drive.
I don't use WD drives, but I -think- they have (on their website) some kind of "utilities" app for managing their drives.

You might take a look and see if this is the case.
If you do find such an app, download it and see if that will allow you to erase the ENTIRE drive.

 

[LuisN]

What model is your drive? It seems to be an external 2xdrives raid enclosure.

 

[gilby101]

It seems to be an external 2xdrives raid enclosure.

I am sure you are right. The WD20NPVX is a 2 GB drive.

Thnderbolt 2 Western Digital 4tb HDD

It looks like your 4TB is two disks inside one enclosure. You can do tricky stuff with RAID, but for Time Machine (or any other backup product) you want simplicity so that disaster recovery is straight forward. So my advice:

Continue to use one 2TB for data and use the other 2 TB for Time Machine.