Add the dotnet product feed

Before installing .NET, you'll need to register the Microsoft key, register the product repository, and install required dependencies. This only needs to be done once per machine.

Open a terminal and run the following commands:

sudo rpm -Uvh https://packages.microsoft.com/config/rhel/7/packages-microsoft-prod.rpm

Install the .NET Runtime

Update the products available for installation, then install the .NET Runtime.

In your terminal, run the following commands:

sudo yum update

sudo yum install aspnetcore-runtime-2.1

The previous command will install the .NET Core Runtime Bundle, which includes the .NET Core runtime and the ASP.NET Core runtime. To install just the .NET Core runtime, use the dotnet-runtime-2.1 package.

参考 ：https://dotnet.microsoft.com/download/linux-package-manager/centos/runtime-2.1.0

使用上面的介绍成功安装了.net core运行时，除此之外还参考了以下网址：

https://blog.csdn.net/hailang2ll/article/details/79759241

https://www.cnblogs.com/niklai/p/5735008.html

https://www.cnblogs.com/GreedyL/p/7422796.html

https://www.cnblogs.com/imstrive/p/9674576.html

https://www.cnblogs.com/tangjiaoshu/p/9866096.html    使用守护服务（Supervisor）保持dotnet进程的运行