We have Windows Server 2008R2 and Windows 2012 VMs running .NET apps built over several years. They utilize DLLs built using System.Configuration to read a config file with passwords, database connection strings, environment variables to control application behavior depending on the environment (DEV, UAT, PROD, etc), your typical legacy grab bag that makes it difficult to migrate to the cloud. DLLs shared among multiple IIS apps/sites are stored in the Windows Global Assembly Cache.
Docker seems like a great solution to extract out each site (or even a specific app within a site), build a self-contained image and deploy that on, say, AWS ECS with all the benefits thereof.
But they don’t talk about how to include global assemblies in the image.