I would like to be able to use rustup in an offline manner. I have read the instructions about how to install rust manually but I have a set of 10+ machines that will need to be setup with a rust development environment that are all on an airgapped network isolated from the internet. For example, the machines are centos and to get them updates I rsync the centos repos and then manually transfer the repo contents to a web server on the offline network. Can I do a similar thing to get rustup to work? In addition, some of the dev tools like RLS and the visual studio code integration really need rustup to work correctly. I have already found some examples of how to get cargo to work in an offline scenario but I need some help with rustup.