Containerization is a lightweight alternative to full machine virtualization that involves encapsulating an application in a container with its own operating environment.
If you plan on using the nginx server to front end you IRIS instance (as opposed to the standard apache web gateway install) you will need to add a few configuration options into the CSP.conf file in order for all urls to work. It took me a little bit to figure this out but this seems to be the configuration that works.