ensure the hostname of the machine didn't change between installer runs
The installer modules use the $fqdn fact in many places, esp also when generating certificates and stuff.
Sometimes, the user would change the hostname of the machine where Foreman/Katello/Proxy is installed which might lead to problems because the installer will try to create new certificates which might not be desired.
I think the installer should check that the current value of $fqdn matches what is in the answers already and warn the user about the situation.
This could be implemented as a pre-hook.