How to move Rails admin to a separate domain?

Question

Ruby on Rails

Hello!
Tell me how to move Rails admin to a separate domain?
Several sites are spinning on one application, for example site1.com, site2.com, etc.
The path to folders with view templates is determined through prepend_view_path
All sites are typical and work from one database
I don’t understand how to make Rails admin work from the same application, but give it my own domain, such as sites-admin.com