My homelab boots off of cheap USB sticks and has done so since 2016.
I easily upgraded my vCenter (VCSA for the win), but could not get Update Manager to upgrade my hosts, it kept throwing an ‘unable to run upgrade script’ error. I tried command-line upgrade without success, then I tried dropping the ISO image on the USB stick with Rufus, booting off the stick and having the installer overwrite the boot image with the installation. I’ve done this same process many times over the past 4 years without issue. However, it kept failing this time. The installation would progress to various percentages, but never beyond 70%
I’ve been working with VMware products since the 3.0 days and I never knew this, thank you to William Lam for his troubleshooting suggestion in VMware’s slack channels. When the progress bar of the installation screen is up, you can press Alt+F1 and get a command prompt. Then you can log in with root and no password. From there you can navigate the filesystem and tail logs, including the install log and vmkernel log. I saw lots of storage errors in the vmkernel log, timeouts and retries.
I then yanked one of the SSD drives in my Synology out and popped it into the host. vSphere 7 installed without issue. Looks like I either need to buy some high-end USB drives, or maybe use this problem to justify swapping out some of the smaller drives in the Synology with larger ones. Then I can rotate the smaller ones into service as boot drives in the hosts.