Installing ESXi – Disk-less, CD-less, Net-less

When installing some new lab hosts the other day, I had bit of a situation. My hosts were in an isolated (new) network environment, they didn’t have CD/DVD drives and they were diskless. So, how do I install ESXi to these new hosts?

By far the simplest way to get ESXi up and running is simply burning the ISO to a CD and booting it from the local CD drive, but that wasn’t an option. Another option may have been to use a remote management capability (ILO, DRAC, RSA etc) but these hosts didn’t have that capability either. I prefer to build my hosts via a network boot option, but as I stated, these were on a network without any existing infrastructure (no PXE boot service, DHCP services, name resolution etc).
However, there’s a really simple way to get ESXi installed in an environment like this…

Did you know that ESXi is (for the most part) hardware agnostic? The hypervisor comes prebuilt to run on most common hardware and doesn’t tie itself to a particular platform post installation. I find the easiest way to get around the constraints listed above is to deploy onto USB storage from another machine and simply plug this USB device into the new server to boot. Usually, this “other machine” is a VM running under VMware Fusion or Workstation! Here’s the five easy steps:

  1. Build a new “blank” VM and use the ESXi ISO file as the OS so Fusion or Workstation can identify it as an ESXi build
  2. As the VM boots up, make sure you connect the USB device to the individual VM
  3. Install ESXi as normal, choosing the USB storage as the install location
  4. Shutdown the VM after the installer initiates the final reboot.
  5. Dismount / Unplug the USB device from the “build” machine and plug it into the host you wish to boot.
  • Chris Chua

    Great post. Recently a colleague needed to build out some blades at a Cisco lab so I used some spare hosts to pxe boot to sd cards. I’ll definitely try using workstation to load the image to a usb. I’m also thinking about loading my kickstart vm on to workstation and trying a crossover cable.