What is a valid example of a vSphere Update Manager upgrade?
A.
A VMware Tools upgrade on a Fault Tolerant machine with automatic snapshots.
B.
Upgrading and patching multiple ESXi hosts simultaneously in a selected cluster.
C.
Upgrading an ESX 4.1 host to ESXi 5.x with a sufficent boot partition.
D.
An ESXi 5.x host update with automatically deleted snapshots.
You cannot use Update Manager to upgrade a host to ESXi 5.0 if the host was previously upgraded from ESX
3.x to ESX 4.x. Such hosts do not have sufficient free space in the /boot partition to support the Update Manager
upgrade process. This problem also affects some 4.x ESX hosts, even if they were not previously upgraded
from ESX 3.x. Hosts must have more than 350MB of free space in the /boot partition to support the Update
Manager upgrade process. If the host that you are upgrading does not have more than 350MB of free space in
the /boot partition, use a scripted or interactive upgrade instead.
http://www.uccx.net/wp-content/uploads/2011/11/vsphere-esxi-vcenter-server-50-upgrade-guide.pdf