.NET Core 2.0 was released mid August 2017. It has now reached end of life (EOL) and will no longer be supported by Microsoft.
.NET Core 2.1 was released towards the end of May 2018 and .NET Core 2.0 reached EOL on October 1. This was supposed to happen on September 1 but was pushed by a month since users experienced issues in upgrading to the newer version.
.NET Core 2.1 is a long-term support (LTS) release and should be supported till at least August 2021. It is recommended to upgrade to and use .NET Core 2.1 for your projects. There are no major changes in the newer version.
.NET Core 2.0 is no longer supported and updates won’t be provided. The installers, zips and Docker images of .NET Core 2.0 will still remain available, but they won’t be supported. Downloads for 2.0 will still be accessible via the Download Archives. However, .NET Core 2.0 is removed from the microsoft/dotnet repository README file. All the existing images will still be available in that repository.
The ‘LTS’ releases contain stabilized features and components. They require fewer updates over their longer support release lifetime. The LTS releases are a good choice for applications that developers do not intend to update very often.
The ‘current’ releases include features that are new and may undergo changes in the future based on feedback/issues. They give access to the latest features and improvements and hence are a good choice for applications in active development. Upgrades to newer .NET Core releases is required more frequently to stay in support.
Some of the new features in .NET Core 2.1 include performance improvements, long term support, Brotli compression, and new cryptography APIs.
To migrate from .NET Core 2.0 to .NET Core 2.1, visit the Microsoft website. You can read the official announcement on GitHub.
Note: article amended 08.10.2018 - .NET Core 2.0 reached EOL on October 1, not .NET Core 2.1. The installers, zips and Docker images will still remain available but won't be supported, not unsupported.
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