Allow ESXi to talk to VMware
esxcli network firewall ruleset set -e true -r httpClient
Enter the folioing in the ESXI cli to list updates available
esxcli software sources profile list -d https://hostupdate.vmware.com/software/VUM/PRODUCTION/main/vmw-depot-index.xml | grep 6.0.0-2015
Now find the update you want to install, normally they end in standard. Enter the following to update
esxcli software profile update -d https://hostupdate.vmware.com/software/VUM/PRODUCTION/main/vmw-depot-index.xml -p nameofupdatetoinstall
Then reboot !