Now that weвЂ™ve covered the basics, the question almost answers itself: SSH into a Docker container would be very much like SSH into localhost.Дocker containers can basically be used in two ways: This is what makes Docker images so lightweight and fast. WhatвЂ™s being virtualized is the execution environment: basically an OS in its own space. So, what hardware is being virtualized then? None!

Notice how you donвЂ™t specify anything about the underlying hardware. RUN curl -sSL | bash -s stable вЂ“ruby=2.1.1 LetвЂ™s take this one as a typical example: FROM ubuntu:13.10 Differences Between Virtual Machines and Docker ContainersДЄnother way to start grasping the difference between Docker and a VM is to look at the Dockerfile. With Docker, this same principle is extended to any language you want. Think about it this way: What does it take to run a Java program? A JVM. You could think of Docker as a generalization of the Java Virtual Machine. They are self-contained execution environments. Your VM engine is simulating a whole hardware set and then running a potentially different OS on top of it.Дocker containers are not simulated hardware. The main difference is that, to the operating system, a VM is not really distinguishable from another physical computer on your LAN. The problem is, Docker containers are not VMs.

Now youвЂ™re switching to Docker, and youвЂ™re looking for a way to do the same and be on your way. In this scenario, youвЂ™re used to starting your work by getting into the VM and running a bunch of commands within it. To SSH or Not to SSH into a Docker ContainerДЄs I said, IвЂ™m assuming you come from a background where virtual machines are a common thing. And finally, IвЂ™ll show you how you could SSH into the Docker container should you absolutely need to. Then IвЂ™ll show you some alternatives for how you can achieve your goal the Docker way. IвЂ™ll start by explaining the main differences between a virtual machine and a Docker container. Just ask yourself: Why would you SSH into a container? Simply to execute some commands within it, right?ДЄfter reading this article, youвЂ™ll have a much clearer picture of why you donвЂ™t need to SSH into the container to do that. Now I have to tell you something that might be a little shocking: ThereвЂ™s most likely no need to SSH into your Docker containers. If thatвЂ™s the case (or close to it), then I have good news for you: I was in your shoes not so long ago.

IвЂ™ll take a bold guess here and bet that, until recently, your local dev environment involved some sort of virtual machine engine-Vagrant, maybe? If you're reading this, youвЂ™re probably just getting your head around this Docker thing.

Docker run image as daemon