I would like to install several instances of Odoo on a single Ubuntu Linux server.  The end result would be a test, prototype and production configuration.  The test instance would have demo data and is where any updates, bug fix, etc would be applied for initial testing and evaluation.  The prototype instance would have copied production data and is where the updates and bug fixes would be applied once they pass thru the test instance.  Finally the updates and bug fixes would be applied to production.  Everything is sitting behind Nginx.  Each instance will be accessed from a unique sub-domain URL, for example test.domain.com, proto.domain.com, and prod.domain.com.  Each instance should be on a different port and should be able to be started and stopped independently.  

How do I install multiple instances of Odoo on the same server and configure it to run on different ports?

How can I take updates to a specific instance of Odoo from github?

How do I copy the application data from one instance of Odoo to another instance of Odoo so I know the code levels match?

Thanks.