For managing omnibus installs, there is one central configuration file called gitlab.rb. You need to create it or copy an example. There is a template available that you can find at https://gitlab.com/gitlab-org/omnibus-gitlab/blob/master/files/gitlab-config-template/gitlab.rb.template. It isn't updated after upgrades. In large parts of this chapter, I will quote and discuss parts of this file.
The code examples for this chapter are available in this book's GitHub repository at https://github.com/PacktPublishing/Mastering-GitLab-12/tree/master/Chapter13.
