This post should hopefully be the first one in a series revolving around my new vSphere homelab. I have been running vSphere nested labs for quite a while, self-built or using the mighty Autolab, but recently I had both the need and the opportunity to put together a small “all-physical” lab. I will publish a post in the coming weeks with more details about its architecture and setup (hey! I’m still building it!) but I decided to pull the trigger and document a little inconvenience I managed to overcome quite easily. I hope you might find this info useful!

My lab runs on Intel NUC Kits, specifically on the latest model, the i5-based DC53427HYE. Again, I’ll be happy to give you more details and feedback in the future, but for now let’s just say that, for the sake of successfully installing ESXi 5.1 on this hardware, I needed to start the installation by booting from an USB drive created from a customized ISO image which included the NUC’s Network Card drivers.

The procedure to create such a custom ISO image involves a very nifty tool called ESXi Customizer, the Intel NIC Driver in .vib format and, of course, the standard ESXi 5.1 ISO. The whole process is described in detail here, where links are provided to dowload all the bits and pieces.

As soon as the Custom ISO was ready (it took only a few seconds) I went for Unetbootin to make a bootable USB thumb drive to boot from. I have used Unetbootin in the past successfully, using the standard ESXi 5.1 ISO as the source image, and it always worked. This time though it didn’t. Only a few files were copied onto the USB drives (the process was surprisingly too fast), de facto making it useless. Mmmh. Weird.

Then I remembered of another cool tool I use to create bootable USB drives with the latest and greatest Linux distributions: Linux Live USB Creator. LiLi (that’s its friendly name) recognised the ISO as “VMware ESXi 5.1” but refused to proceed as, according to the tool, the image was “corrupted”. Mmmh… Even weirder.

I began to fear the worse… then something come to my mind: Rufus! This one is another tool, very similar to Unetbootin, but faster and with a bunch of extra useful features. Needless to say, it worked where the other tools have failed!

This is what I did:

I grabbed a spare USB drive and attached it to my laptop, then launched Rufus (the latest version is and selected the following options (exactly as showed in the screenshot below):

  • MBR partition scheme for BIOS or UEFI Computers
  • FAT32 File System
  • 4096 bytes Cluster Size
  • Quick Format
  • Create a Bootable Disk using: ISO Image


Then I selected my Custom ISO Image and I received this warning:


I decided to leave the ISO unmodified, and you should do the same, so be sure to select “No” when prompted.

*** UPDATE *** I found out that with ESXi 6.0 it is advisable to replace the “obsolete” menu.c32 with the newest one, otherwise the USB key won’t boot properly. So you should answer YES when prompted in the above dialog and let Rufus download the right file.

Rufus tool only a couple of minutes to prepare the bootable USB drive.

All I can say is that it saved my day and I successfully installed three Intel NUC ESXi Hosts using this thumb drive!


If you like this post, please share it!

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.