Mac USB Harddrive formatting using command line tools

I recently bought a 3TB My Passport USB Hard Drive to use as storage for my cloud storage (OneDrive , Google Drive, iCloud). I tried setting up this device using disk utility in Mac but always ended with error

“Erase Process has failed. Press done to continue”

I just couldn’t get this done using the UI tool.

I used the following command line instructions and was able to get it done.

$ diskutil list

/dev/disk0 (internal):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                         2.0 TB     disk0
   1:                        EFI EFI                     314.6 MB   disk0s1
   2:          Apple_CoreStorage Macintosh HD            2.0 TB     disk0s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3

/dev/disk1 (internal, virtual):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                  Apple_HFS Macintosh HD           +2.0 TB     disk1
                                 Logical Volume on disk0s2
                                 Unlocked Encrypted

/dev/disk2 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:     FDisk_partition_scheme                        *3.0 TB     disk2
   1:               Windows_NTFS New Volume              2.2 TB     disk2s1

Notice the column called Identifier. In my case the drive , I wanted to erase had Identifier disk2. It is important to make sure the identifier is correct

Next, unmount the disk

$ diskutil unmountDisk force disk2
Forced unmount of all volumes on disk2 was successful

Next, overwrite the MBR to be Zeros so that Mac OS creates new partition

$ sudo dd if=/dev/zero of=/dev/disk2 bs=1024 count=1024
1024+0 records in
1024+0 records out
1048576 bytes transferred in 0.647115 secs (1620386 bytes/sec)

Finally, Erase the volume creating new partitions

$ diskutil partitionDisk disk2  GPT JHFS+ "MyUSBDrive" 0g

Started partitioning on disk2
Unmounting disk
Creating the partition map
Waiting for partitions to activate
Formatting disk2s2 as Mac OS Extended (Journaled) with name MyUSBDrive
Initialized /dev/rdisk2s2 as a 3 TB case-insensitive HFS Plus volume with a 229376k journal
Mounting disk
Finished partitioning on disk2
/dev/disk2 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *3.0 TB     disk2
   1:                        EFI EFI                     314.6 MB   disk2s1
   2:                  Apple_HFS MyUSBDrive                3.0 TB     disk2s2

Voila and it’s done.

I hope it helps if anyone else encounters similar issue

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