As an update I ran the 6.0.0 installer, and that one found the USB stick. Very weird.
Installed 6.5 now on an HDD.
This bit me bad. I used VUM in VCSA 6.5 to upgrade a host not realizing it was installed on USB key. Shouldn't be an issue, except VUM pushed the update package out and when it went to install it couldn't find the disk/etc. and ended with an error on some kickstart script blah blah. When I booted off of the ISO directly (now that the host was infinitely looping on the VUM install) it showed no USB devices. I installed on HDD but still, something that should be checked beforehand! Had to set the host up manually.
Seeing the same issue when trying to upgrade a Gigabyte GA7-PESH1 from 6.0 Update 2 to 6.5.
After some testing, the ISO/DVD installer does not work. However, the offline vib-based installer works just fine if you already have 6.0 installed.
esxcli software profile update --depot=/vmfs/volumes/<my datastore>/VMware-ESXi-6.5.0-4564106-depot.zip -p=ESXi-6.5.0-4564106-standard
So, probably bunch of people has same issue. So, how can we install esxi 6.5 to usb stick. As I read, they change the USB driver method and they put only vmkusb driver instead of XHCI/EHCI/UHCI/OHCI.
But, there is no solution for that. They still say, first install it then disable it if you want. But there is nothing about how to disable it before installing.
This method did the job - not a complete solution, but a nice and easy workaround!
My story, may be help:
I have server ESXi6 with USB flash drive boot. I did upgrade through VUM to 6.5. On reboot had error: device naa.2** can't be read.
On start clean install local USB flash drive not found.
I did run server, on ESXi boot menu did press "Shift+O", add "preferVmklinux=TRUE" to the end of string. After this upgrade was finished. Now a host normal boot from 4GB USB flash drive.
If you still see this issue, provide logs such as vmkernel.log and ouput lsusb -v information will be help.
And if possible, provide the device information to get the right one on the market for inverstrigation will be best.