2. About Docker

2.1. What is docker?

../../_images/docker-vs-lxc.png

Figure 42. Docker vs LXC

2.2. Architecture

Guest

Container running on Docker Engine

Host

Server running Docker Engine, see also Docker 0

Docker 0

Server running Docker Engine

2.3. Docker image vs container

Image

Ready to run Operating System with pre-installed software

Container

Running instance of an image

2.4. Layers

Layer

Diff between outputs of Dockerfile RUN command while building an image

../../_images/docker-layer-images.png

Figure 43. Layers

../../_images/docker-layers.png

Figure 44. Layers

../../_images/docker-container-layers.jpg

Figure 45. Container Layers

../../_images/docker-container-layers.png

Figure 46. Container Layers