Introduction

Containers have become the most popular solution for developers and IT folks in modern software development and deployment. They have been growing in popularity among developers and organizations looking for effective software delivery solutions because of their low weight, portability, and scalability.

However, in the case of Windows container hosting on a Linux environment, there are significant challenges due to existing operating system differences and compatibility issues. To overcome this gap and take advantage of the benefits offered by both Windows and Linux environments, developers and system administrators are looking for innovative solutions.

One such solution involves leveraging virtualization technology like Docker containers. This means using special tools to create a setup where Windows containers can work smoothly alongside Linux containers. This enables developers to overcome the differences between these two operating systems, enabling them to work together smoothly.

In this blog, we'll take an extensive journey to investigate the complex process of hosting Windows containers on Linux using innovative virtualization techniques. We're going to go over the basics of setting up the necessary tools, creating a Windows container within a Linux host, using RDP, and configuring it to seamlessly host Windows containers.

Let's clear some of the terminologies first...

Windows Containers: To run applications on Windows servers, Containers are used as they are lightweight, portable, and provide isolated environments, for a consistent runtime environment for software.
LinuxHost: It is the primary environment for hosting and managing applications and services is the computer system that runs Linux.
Virtualization: It's a technology that allows multiple operating systems to run on the same physical machine. It creates a virtualized environment that isolates each operating system from other systems and the host machine.
Docker: It serves as a toolkit to streamline the creation, deployment, and operation of applications within containers.
Containerization: Think of containerization as a magic box that holds everything that an application needs to work, making it so easy to carry and run on different computers.
RDP: It allows you to communicate over the network with a Graphical User Interface for another computer. The user will be able to control the remote computer as if they were physically present on that machine when he starts an RDP session.

While Linux is great for hosting containers, the direct hosting of Windows containers on Linux poses compatibility and technical challenges that need to be addressed.

Let's understand why direct hosting of Windows containers on Linux is not feasible.

Windows and Linux are incompatible with Direct Container Hosting because of their different kernel architectures and calls to the system. The Windows container relies on Windows-specific features and APIs that are not available in the Linux kernel, which makes it impossible to run smoothly on a Linux host. The containerization is dependent on the kernel of the Host Operating System, and since Windows containers are tightly bound to the Windows Kernel, it would be impossible to install them upon Linux. Essentially, there is a fundamental barrier to the direct hosting of Windows containers on Linux because of the differences in the structure of the kernel and the functionality of the system between Windows and Linux.

Now that we have a basic understanding of Windows containers, Let's take a look 🔍at how to host Windows containers on Linux:

Let's Get Started: A Walkthrough of the Process

Pulling a Windows Container Image 🖥️

To fetch a Windows container image from Docker Hub, let's go through the following steps:

First, open an on your Linux host to execute commands.
Input the following code to pull a specific version of the Windows Server Core from Docker Hub:
```
 docker pull mcr.microsoft.com/windows:11
```
By running this command, you will successfully download the Windows Server Core image tagged with ltsc2019.
Verify the pulled image to confirm its availability by listing all Docker images using:
```
 docker images
```
This will display the Windows container image in the list of Docker images on your Linux host.

Configuration and Setup 🛠️

To configure Docker on Linux for Windows container support, let's take the following steps:

Check for virtualization support on the Linux host by running the command:
```
 egrep -c '(vmx|svm)' /proc/cpuinfo
```
Ensure that the output is greater than 0, indicating the presence of virtualization support.
Ensure that Hyper-V is enabled in the BIOS settings of your host machine, with steps varying depending on the BIOS firmware.
Update the package lists on your Linux host using:
```
 sudo apt-get update
```
Proceed to install Docker, QEMU, KVM, and bridge-utils by executing the following command:
```
 sudo apt-get install -y docker.io qemu-kvm bridge-utils
```
- QEMU: an open-source emulator and virtualizer for running virtual machines.
- KVM: a Linux kernel module offering hardware virtualization support.
- bridge-utils: utility tools for configuring and managing network bridge devices.

Running a Windows Container on Linux 🚀

Here are detailed steps to run a Windows container on a Linux host using Docker:

Utilize the previously fetched Windows container image to create a new container with this command:
```
 docker run -d --name my_windows_container mcr.microsoft.com/windows:11
```
This command establishes a new container named 'my_windows_container' using the acquired Windows Server Core image, detached in the background.
Access a shell within the running container to interact and execute commands by utilizing:
```
 docker exec -it my_windows_container cmd
```
This command opens a shell within the active Windows container, enabling interaction and command execution within the container environment.

Following these comprehensive steps, you can proficiently pull a Windows container image from Docker Hub, configure Docker on Linux for Windows container compatibility, and execute a Windows container on a Linux host using Docker, with each step detailed with relevant commands and parameters for clarity. 🚀

Conclusion

The strengths of both operating systems are combined in the path to host Windows containers on Linux. We have explored how these innovative technologies can bridge the gap between two fundamentally different operating systems, enabling us to take advantage of what both worlds offer. We unlocked a world of possibilities where Windows and Linux containers coexist peacefully, paving the way for increased flexibility and effectiveness in software development and deployment by using tools like Docker and KVM.

How to host Windows container on Linux

Bridging the Gap: Hosting Windows Containers on Linux

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