How's Docker Running on Your Computer

In my last blog, we had a long discussion about the relationship between a container and an image. Furthermore, we spoke a bit about the separation or the isolation of these resources through a technique called name spacing.

And we also said that we could limit the number of resources used by these control group things as well. But these features of the name spacing and control groups are not included by default with all operating systems.

These features of name spacing and control groups are specific to the Linux operating system.

So name spacing & control groups to belong to Linux not to Windows, not to Mac OS.

So that might make you kind of question or wonder how are you running Docker right now.

We are running a Docker client, and we are running Docker containers on a Mac OS or Windows operating system.

How is that happening????

If these are Linux specific features Well here’s what’s happening behind the scenes.

When you installed Docker for Windows or Docker for Mac, you installed a Linux virtual machine.

So so long as Docker is running you technically have a Linux virtual machine running on your computer. Inside of this virtual machine is where all these containers are going to be created.

So inside the virtual machine, we have a Linux Kernel and that Linux kernel is going to be hosting running processes inside of containers and it’s that Linux Kernel that’s going to be in charge of limiting access or kind of constraining access or isolating access to different hardware resources on your computer.

You can actually see this Linux virtual machine in practice by opening up your terminal right now.

And if you run that docker version command again and look at your server you’ll notice that there’s actually an OS and tree on here.

And you’ll notice that it probably doesn’t have your operating system listed.

So that is kind of specifying that I’m running a Linux virtual machine and that’s what’s being used to host all these different containers that you and I are going to be working with.

That's it, Thanks 😊