In the process of building out a new small VMware Lab using Intel NUCs. First thing we needed to do, was to get the ESXi installer onto a USB drive from a Mac.

To do this, we need the ESXi installer ISO file and a >8GB USB Drive.

Insert the USB Drive into your Mac (Most likely via a super expensive adaptor…)

From a Terminal (I’m using iTerm2) enter the following command:

diskutil list

This will provide a list of connected Drives – take a note of the Drive Number, of the USB Drive (In my case here, it is Disk2)

To make the USB bootable on the NUC, we need to format it using FAT32 with MBR, using the following command NOTES:

  1. Substitute Disk number with the relevant disk#
  2. The Name you specify in Quotes MUST be in Capitals
diskutil eraseDisk MS-DOS "ESXIBOOT" MBR disk2

Now, unmount the USB Drive (Using correct Disk#):

diskutil unmount /dev/disk2

We need to make the Partition as Bootable using the Command Line Partitioner (You must use Sudo):

sudo fdisk -e /dev/disk2
  • To Flag the First Partition as bootable, type: f 1
  • Write the changes by typing: write
  • Quit by typing: quit

Now we need to copy the contents of the ESXi Installer ISO to the USB Drive. Mount the ISO. I have just Double Clicked the ISO file I downloaded and it is mounted in Finder.

Select All Files and Copy to the USB Drive

Once all files have copied, locate the ISOLINUX.CFG file and rename to SYSLINUX.CFG

Open SYSLINUX.CFG with a Text Editor, I am using the Default TextEdit

We need to Add -p 1 to the end of the line which starts with APPEND

Click OK ono the Message that comes up – I re-opened the File just to confirm it had written correctly. You can now Unmount the USB Drive from your Mac

Thanks to Virtuallywired for the help with this!