Edition 0 Updated to asp. Net core 0

Development
: The priority is the ability to quickly iterate and debug changes, and where size is 
secondary. 
2.
Build
: The priority is compiling the application, and the image includes binaries and other 
dependencies to optimize binaries. 
3.
Production
: The focus is fast deploying and starting of containers, so these images are limited 
to the binaries and content needed to run the application. 
The .NET team provides four basic variants in 
dotnet/
 (at Docker Hub): 
1.
sdk
: for development and build scenarios 
2.
aspnet
: for ASP.NET production scenarios 
3.
runtime
: for .NET production scenarios 
4.
runtime-deps
: for production scenarios of 
self-contained applications
 
For faster startup, runtime images also automatically set aspnetcore_urls to port 80 and use Ngen to 
create a native image cache of assemblies. 
Additional resources 
•
Building Optimized Docker Images with ASP.NET Core
https://learn.microsoft.com/archive/blogs/stevelasker/building-optimized-docker-images-with-
asp-net-core
 
•
Building Docker Images for .NET Applications
https://learn.microsoft.com/dotnet/core/docker/building-net-docker-images
 
Use a database server running as a container 
You can have your databases (SQL Server, PostgreSQL, MySQL, etc.) on regular standalone servers, in 
on-premises clusters, or in PaaS services in the cloud like Azure SQL DB. However, for development 
and 
test environments, having your databases running as containers is convenient, because you don’t 

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CHAPTER 5 | Designing and Developing Multi-Container and Microservice-Based .NET Applications 
have any external dependency and simply running the 
docker-compose up
command starts the whole 
application. Having those databases as containers is also great for integration tests, because the 
database is started in the container and is always populated with the same sample data, so tests can 
be more predictable.