How to install multiple versions of .NET Core side by side on ubuntu

Question

We have an app, written in .NET Core rc2 running on an acceptance environment (linux server). Recently our client ran their own performance tests, which turned out to completely break the application. We couldn't reproduce it ourselves for several reasons:

1. We develop on windows
2. We have since migrated from rc2 to 1.0.0.

On windows, we couldn't reproduce in either our new version (1.0.0) or rc2. So we tried to reproduce it on a linux machine. on 1.0.0 we couldn't reproduce their results either, but when we tried to actually test against rc2 (an older version of our app, obviously) we ran into a really annoying problem: I don't seem to be able to install 1.0.0 and rc2 side by side, even though the error message implies it's possible. Below is the error message

The specified framework 'Microsoft.NETCore.App', version '1.0.0-rc2-3002702' was not found.   - Check application dependencies and target a framework version installed at:       /usr/share/dotnet/shared/Microsoft.NETCore.App   - The following versions are installed:       1.0.0   - Alternatively, install the framework version '1.0.0-rc2-3002702'. 

Basically, we want to be able to check the version currently running on acceptance of our app (rc2) on a linux machine, but we are struggling with actually getting rc2 on it.

Thanks. If anything is unclear, post your question in the comments.

EDIT: I tried building it as a standalone deployment, but then I get the following error:

Errors in /home/nicolaas/Projects/digipolis-survey-engine/Digipolis.FormEngine/Digipolis.FormEngine.Response.API/project.json     System.AppContext 4.1.0-rc2-24027 provides a compile-time reference assembly for System.AppContext on .NETCoreApp,Version=v1.0, but there is no run-time assembly compatible with ubuntu.15.10-x64.     System.Runtime.InteropServices.RuntimeInformation 4.0.0-rc2-24027 provides a compile-time reference assembly for System.Runtime.InteropServices.RuntimeInformation on .NETCoreApp,Version=v1.0, but there is no run-time assembly compatible with ubuntu.15.10-x64.     One or more packages are incompatible with .NETCoreApp,Version=v1.0 (ubuntu.15.10-x64). 

This is to be expected as rc2 is actually not installed on the machine, and I want to build it on the linux machine

Answer 1

Simply use the dotnet install script: https://docs.microsoft.com/en-us/dotnet/core/tools/dotnet-install-script

This is a good tutorial: https://www.hanselman.com/blog/SideBySideUserScopedNETCoreInstallationsOnLinuxWithDotnetinstallsh.aspx

Answer 2

This has been working for us.

1. Installing multiple versions of dotnet runtime to separate directories.

2. For the latest runtime installation, add symlinks for each of the older runtimes. For example, for older runtime 1.1.2 we create the symlink /path/to/dotnet-latest/shared/Microsoft.NETCore.App/1.1.2 --> /path/to/dotnet-1.1.2/shared/Microsoft.NETCore.App/1.1.2

3. Run dotnet from the latest runtime installation and it should pick up the appropriate runtime.

Note that this is equivalent to what happens with the Windows installer. The new runtime is added to the shared installation. A similar approach can be used to get support for multiple sdks from a single installation by adding the appropriate symlinks in the sdk subdirectory.