Create a Bootable ESXi Installer USB Flash Drive on MacOS

In this post I’ll show how to create a bootable ESXi Installer USB flash drive on MacOS without any 3rd party software. I’ve done this many times on Windows using Rufus, but I show now I demonstrate how it can be done using only the Terminal on MacOS.


Prerequisites

  • Download the ESXi Installation ISO (I used ESXi 6.7 Update 3)
  • A USB Flash Drive Minimum 8GB

Step 1

Open Terminal and list the mounted disks using the diskutil list command.

diskutil list

Step 2

Insert the USB Flash then run the diskutil list command again.

diskutil list

You should now see another disk show up, in my case disk3. Take note for the disk#.


Step 3

Now we need to format the drive with filesystem FAT32 and partition map MBR using the following command. Don’t forget to use the disk# number obtained in step 2.

diskutil eraseDisk MS-DOS "ESXI" MBR disk3

Step 4

Unmount the USB Drive, Note: This is not the same as Eject. Don’t forget to use the disk# number obtained in step 2.

diskutil unmountDisk /dev/disk3

Step 5

Start the command line partitoner fdisk in interactive mode (You will need administrative privileges for this).

sudo fdisk -e /dev/disk3
  1. Flag the first partition on the volume as active and bootable.
  2. Write the changes.
  3. Quit fdisk.
f 1
write
quit

Step 6

Mount the ESXi Installation ISO and copy all the contents from the ISO to the USB flash drive.


Step 7

Locate the file ISOLINUX.CFG on the flash drive and rename it SYSLINUX.CFG file.


Step 8

Edit the SYSLINUX.CFG file with TextEdit, Don’t use a Word program it will mess up the file. Find the line starting with APPEND -c boot.cfg and append -p 1 to it.

APPEND -c boot.cfg -p 1

Save and close the file and eject the USB flash drive.


Step 9

I booted the ESXi installer on my Intel NUC Skull Canyon successfully.


Here’s a Tip! the installer loads the files into memory so you can choose the same USB drive to install ESXi and boot from. Hope you enjoyed this guide.

3 comments Add yours
  1. Please disregard, the file must be hidden or something. I can’t see it using Finder, but it’s there if I use Terminal app

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