04 August 2009

Installing ESX 4 from USB Flash

The target server had a CD drive and I only had a DVD .iso file that was about 835Mb. I discovered that the server's BIOS would allow me to boot from a USB flash drive. I used unetbootin to burn the .iso file to my USB drive. Next, and this is the important part, I booted from the USB drive and pressed the Tab key when presented with the boot options for ESX. That then brings up the standard line of options to pass into the kernel. I appended askmedia to that line. The askmedia option allows one to specify that the install media is hosted and available elsewhere, for example, HTTP, FTP, NFS, or USB. Of course, I selected USB when prompted and the rest of the install proceeded automatically with no problems.


  1. For some reason, this wouldn't work for me the first time. The server didn't recognize that it was a bootable USB drive. I had to re-format the USB drive in Windows and THEN use unetbootin to re-burn the .iso to it. After that, it worked great. This is SOOOO much easier of a way to install ESX from USB than the other suggestions out there!

  2. Two questions. When you created the boot usb what option did you choose in unetbootin for distribution? Also when you booted and pressed tab what command did you use?

  3. Thanks for this post Mike. I had some left-over hardware that I needed to convert to ESX that didn't have cd drive. This is really cool !