I want to in place upgrade our Foreman instance (no katello, all in one,
running puppet master) to Puppet 4 AIO.
I am confused what procedure to follow:
- or -
The Foreman Wiki procedure?
Should  not be applicable, what could be the reasoning having this
option for Katello but not Foreman?
 Foreman :: Plugin Manuals
Upgrading from Puppet 3 to 4 - Foreman