Getting vSphere 6.7U3b up and running on a non-UEFI server

Hi all, I thought I share since I went through this yesterday on my HP DL360p G8 in the lab. It started out with the cheap-o USB stick I had installed ESXi on flaking out.. and for those that have had it happen it can be unnerving to say the least. I couldn’t power down VM’s, make changes to the config, etc… I knew what had likely happened and on a reboot.. well, it never came back.

After a quick search I went to Walgreen’s and picked up a new 64GB Sandisk Cruzr, on sale for $18. Easy peasy I thought and swapped out the 8GB PNY (that had served me for 2+ years mind you) and mapped up the newest vSphere 6.7U3 iso to the virtual CDROM in ILO. Booted up, went through install, Cruzer was detected and the install completed in 6ish minutes. Then, after the final install reboot.. It wasn’t booting from the newly installed USB drive?! I tried all the normal things.. Check BIOS, yup USB boot enabled, USB ports enabled.. blaa blaa.. It was just booting from USB and I was running 6.7U3 on it before the old USB drive died..

I turned to Google and found several references to HP DL360p’s G8s having problems with booting from USB and that I should stand on my head while dancing a hula or some such thing to get it working and then NEVER EVER reboot again! Turns out my “vintage” server (released 8 years ago!) doesn’t have UEFI support. In vSphere 6.7 we stopped supporting MBR partitioning when installing ESXi, thus it defaults to GPT formatting and then I found this post:… which pretty much sealed it, I needed a workaround.

Turns out what I needed to do was a 2 step process

  1. Install 6.5 with “formatwithmbr” option.
  2. Upgrade to 6.7U3b.

Install ESXi 6.5 with formatwithmbr

Just like it sounds, once the USB drive is cleaned off, you’ll want to boot up using the ESXi 6.5 installer ISO. In version 6.7+ the “formatwithmbr” option is no longer supported. Once you get to the “Press enter to install screen” you’ll need to press enter and then CTRL-O (that’s an O like Oscar) and you should see a prompt in the bottom left that says “runweasel”. On this line you’ll want to add a space and formatwithmbr and then press enter.

Enter the rest of your information as you normally would, ensuring you select the drive we cleaned off above to install on. Once it’s time for the final reboot, go ahead!

Upgrade to 6.7U3b

Then all you have to do is boot up the ESXi 6.7U3b installer and when you select your installation target it will detect the 6.5 install and ask if you want to Install or Upgrade. Make sure you select Upgrade and let it run through it’s paces.

After a final reboot you’ll be up and running with vSphere 6.7U3b! In the process of writing this post I found another similar one from someone that used to be on my team.. I’ll link it here because there is some decent (dated) info plus I think some of his screenshots are better: Thank you!