Upgrade vCenter

Best practices is always to upgrade vCenter before your ESXi hosts. Download the ISO and upload to your Datastore.

Attach the ISO to the vCenter VM.

Mount ISO

Use Putty to connect to your VCSA and run the following command:

software-packages install --iso --acceptEulas

reboot -r updates
exit

Update ESXi – Fast Method

This is the fastest way, but requires a decent internet connection.

Shut down all your running VM’s and enter Maintenance Mode.

Use Putty to connect to your ESXi host and run the following command:

esxcli network firewall ruleset set -e true -r httpClient
esxcli software sources profile list -d https://hostupdate.vmware.com/software/VUM/PRODUCTION/main/vmw-depot-index.xml
esxcli software profile update -p ESXi-6.0.0-20160104001-standard -d https://hostupdate.vmware.com/software/VUM/PRODUCTION/main/vmw-depot-index.xml

reboot
exit