I found that I had to wipe ESXi completely off the system to install OSX 10.9 on the internal disk of the system because that is the only place and OS that the bios update for this system would run from. Yay apple! Prior to the wipe I had 1 vm that I was able to upgrade to 10.13 without issue.
After updating the bios I wiped the internal SSD and installed ESXi 6.5 u1 w/ the October update. Performance is TERRIBLE now when a VM has a snapshot. On a host with a 1tb SSD , 32gb of ram, 12core processor, it should be fine. 1vm running on the host with macos 10.12.6 with a thick provisioned disk runs fine without a snapshot. Once I take a snap it keeps giving me the pin-wheel ever few seconds. Even a copy of a 5gb file from an SMB share brings it to its knees with the guest responding to key-presses intermittently and the host web interface taking 5-10 seconds to fill in information when navigating around. I'm not sure what the difference is between 6.0 and 6.5, but something is very wrong here.
Anyway, worse luck with 10.13 after the bios update and ESXi upgrade. Booting from 10.13 installation iso I still cannot see the virtual disks. When I run an upgrade of the OS from 10.12.6 to 10.13 the system eventually gets to a reboot where it cannot find any boot disks and gives me the standard vmware blue ansi boot menu. At this point I boot from a 10.12 installation iso to open disk-utility and see what the status is of the disk. The 10.12 ISO sees the internal disk, but with 0 partitions, and lists it as "unformatted". Might be something going on there with APFS.
I'm probably going to end up going to fusion soon w/ me logged into the console 100% of the time to keep the vms running if I cannot figure something out.
