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.
- Download the ESXi Installation ISO (I used ESXi 6.7 Update 3)
- A USB Flash Drive Minimum 8GB
Open Terminal and list the mounted disks using the diskutil list command.
Insert the USB Flash then run the diskutil list command again.
You should now see another disk show up, in my case disk3. Take note for the disk#.
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
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
Start the command line partitoner fdisk in interactive mode (You will need administrative privileges for this).
sudo fdisk -e /dev/disk3
- Flag the first partition on the volume as active and bootable.
- Write the changes.
- Quit fdisk.
f 1 write quit
Mount the ESXi Installation ISO and copy all the contents from the ISO to the USB flash drive.
Locate the file ISOLINUX.CFG on the flash drive and rename it SYSLINUX.CFG file.
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.
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.