Copy an ISO to a USB Drive from a Mac using dd

Attach the target USB drive to your Mac if you haven’t done so yet, then launch the Terminal.

Type the following command to print a list of attached volumes on the Mac:

diskutil list

This may look something like the following, it will be different on every Mac:

/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *1.0 TB     disk0
   1:                        EFI ?EFI?                     209.7 MB   disk0s1
   2:                 Apple_APFS ?Container disk1?         1000.0 GB  disk0s2

/dev/disk1 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +1000.0 GB  disk1
                                 Physical Store disk0s2
   1:                APFS Volume ?Macintosh SSD - Data?    239.5 GB   disk1s1
   2:                APFS Volume ?Preboot?                 339.1 MB   disk1s2
   3:                APFS Volume ?Recovery?                620.3 MB   disk1s3
   4:                APFS Volume ?VM?                      2.1 GB     disk1s4
   5:                APFS Volume ?Macintosh SSD?           15.3 GB    disk1s5
   6:              APFS Snapshot ?com.apple.os.update-...? 15.3 GB    disk1s5s1

/dev/disk2 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                     partition_scheme           *5.3 MB     disk2
   1:                     partition_map                32.3 KB     disk2s1
   2:              FAT_32 THE_DESTINATION    8.2 GB      disk2s2

Unmount the target volume using the following command, replacing the identifier as appropriate:

sudo diskutil umount /dev/(IDENTIFIER)

Example:

sudo diskutil umount /dev/disk2

Format the target drive and ‘burn’ the ISO to that USB volume, this will erase all data on the target drive replacing it with the ISO. This can not be undone!

sudo dd if=/path/image.iso of=/dev/r(IDENTIFIER) bs=1m

For example, with a ISO named ‘tahr-6.0.5_PAE.iso’, and the target USB drive is ‘disk2’, the syntax would be:

sudo dd if=tahr-6.0.5_PAE.iso of=/dev/rdisk2 bs=1m

If you get the following error:

“Operation not permitted”

  • Pull down the Apple menu and choose ‘System Preferences’
  • Choose “Security & Privacy” control panel
  • Now select the “Privacy” tab, then from the left-side menu select “Full Disk Access”
  • Click the lock icon in the lower left corner of the preference panel and authenticate with an admin level login
  • Now click the [+] plus button to add an application with full disk access
  • Navigate to the /Applications/Utilities/ folder and choose “Terminal” to grant Terminal with Full Disk Access privileges
  • Relaunch Terminal, the “Operation not permitted” error messages will be gone.