Running multiple parallel instances of a .NET Core App using dotnet run

I had the same problem and solved it using --no-build option:

dotnet run --no-build <path to .dll> <args>

Please take a look at: MSDN documentation

I've used bat file to run 6 instances of app in one time. Only problem was when I started build of application and immediately run script. So I think you should make sure that build process ended. And then run you bat file with for example dotnet run repeated six times. Your app should be built to execute this file.

start /d "." dotnet run args
start /d "." dotnet run args
start /d "." dotnet run args
start /d "." dotnet run args
start /d "." dotnet run args
start /d "." dotnet run args