I don't recall having this issue when I did a fresh install of 6.0, but with 6.1 when I go to the console and enter:
sudo apt install -y open-vm-tools
I get an error that no candidate is available. It would be great if these tools were available under System Updates or Zentyal Components
RESOLVED: as recommended, after doing apt update -y and apt upgrade -y, open-vm-tools was able to be installed.