Pulling a Windows Image for Docker on Windows Server 2019 has OS compatibility issues

Question

I have recently tried to pull and run a Docker image (that worked on Windows 10) on a Windows Server 2019 instance which failed with the following error message:

The container operating system does not match the host operating system.

I've tried it on the latest version of Windows Server Core and Nano Server from the normal microsoft/windowsservercore and microsoft/nanoserver repositories.

I don't understand because those are Windows Kernels running on a Windows Operating System.

Answer 1

Based on the feedback given on this github issue you have to pull the repository from Microsoft's new Container Registry (mcr.microsoft.com) for a specific version (1809). This version is compatible with Windows Server 2019.

docker pull mcr.microsoft.com/windows/servercore:1809

docker pull mcr.microsoft.com/windows/nanoserver:1809

Also beware that nanoserver no longer has Power-Shell in its base image.

As for why this is happening, I am not sure. Would appreciate if anyone could shed some light on the subject.

Answer 2

This error appears because Windows 10 and Windows Server have different Isolation Modes: Hyper-V Isolation for Win 10 and Process Isolation for Win Server. You can find more here