I new to VMWARE so I don't have much experience with it.
My current setup is quite rudimentary and I'm glad moving to 11.1 didn't break anything apparent. But from what I saw, v11.1 doesn't look like an "update"of 11.0. The upgrade literally uninstalled 11.0 as if 11.1 was a completely new product.
OP is right. It looks like the upgrade operation wiped his network configuration during the installation process. As he mentioned, we don't expect a change of state in the configuration during an "update".