The first Docker book, chapter 4th uses Docker images and warehouse reading notes

The bottom of Docker is a boot file system, Bootfs.

The second layer is the root filesystem rootfs, located on the boot file system.

In the traditional Linux boot process, the root filesystem is first read-only and is switched to read-write mode when the boot finishes and the integrity check is completed. But in Docker, the root filesystem is always read-only, and Docker uses the federated loading technology to load more read-only file systems on the root filesystem layer. Federated loading refers to the simultaneous loading of multiple file systems at once, but only one file system can be seen outside. Federated loading overlays each layer of file systems so that the final file system contains all the underlying files and directories.

Docker makes such a file system mirror. One image can be placed at the top of another mirror. The mirror below becomes the parent image, and the bottom of the image is called the base image.

When Docker launches a container for the first time, the initial read-write layer is empty. These changes are referenced to this layer when the file system changes. For example, if you want to modify a file, the file is copied from the read-only layer below the read-write layer to the read-write layer. The read-only version of the file still exists, but it has been hidden by a copy of the file in the read-write layer. This mechanism is copied as a write-time.

Docker Images #查看所有的docker镜像

The local image is saved under/var/lib/docker, and all the containers are stored in the/var/lib/docker/containers

Docker pull Ubuntu #拉去镜像

Docker run-it--name container name Ubuntu:12.04/bin/bash #可以给镜像加上版本

Mirror split user and top-level mirroring.

Docker images Fedora #查看指定的镜像列表

Docker Search Puppet #查找指定的镜像

　　

Build image

Docker login #登录 (domestic access to the Docker hub is so slow)

　　

The first Docker book, chapter 4th uses Docker images and warehouse reading notes