How to install Docker on Ubuntu

li26598296

　　Docker currently only runs on 64-bits platforms and requires that the kernal version be no less than3.10.
in this tutorial , i use ubuntu 16.04 and the kernal version is 4.13.0-43-generic
you can use this command to find your linux-version and linux-kernal version.

uname -a
cat /proc/version
　　At the first , you need to update your existing list of packages:

sudo apt update
　　Second, you need to install a few prerequisite packages which let apt use packages over HTTPS

sudo apt install apt-transport-https ca-certificates curl software-properties-common
　　add the GPG key for the official Docker repository to your system:

curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
　　Add the Docker repository to APT sources:

sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
　　update the package database with the Docker packages from the newly added repo:

sudo apt-get update
　　After you can install Docker

sudo  apt-get install docker-ce
　　if you have error on apt-get  like this :

you can use this command to find the process using apt , and kill it !

ps aux | grep apt

after that , how can you check that docker is installed ?
you can use this command to chek

sudo service docker start
docker version

　　Than,test that your installation works by running the simple Docker image, hello-world:

root@ubuntu:~# docker run hello-world
Hello from Docker!
This message shows that your installation appears to be working correctly.
To generate this message, Docker took the following steps:
1. The Docker client contacted the Docker daemon.
2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
(amd64)
3. The Docker daemon created a new container from that image which runs the
executable that produces the output you are currently reading.
4. The Docker daemon streamed that output to the Docker client, which sent it
to your terminal.
To try something more ambitious, you can run an Ubuntu container with:
$ docker run -it ubuntu bash
Share images, automate workflows, and more with a free Docker ID:
https://hub.docker.com/
For more examples and ideas, visit:
https://docs.docker.com/get-started/
　　List the hello-world container (spawned by the image) which exits after displaying its message. If it were still running, you would not need the --all option:

root@ubuntu:~# docker container ls --all
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                      PORTS               NAMES
46ea9cb299d4        hello-world         "/hello"            2 minutes ago       Exited (0) 2 minutes ago                        objective_mestorf
1d9c5cbbed49        hello-world         "/hello"            9 minutes ago       Exited (0) 9 minutes ago                        goofy_diffie
fef4ade3de12        hello-world         "/hello"            22 minutes ago      Exited (0) 22 minutes ago                       pensive_brown
6d77512305e5        hello-world         "/hello"            22 minutes ago      Exited (0) 22 minutes ago                       vigorous_heyrovsky

　　Reference:
https://askubuntu.com/questions/15433/unable-to-lock-the-administration-directory-var-lib-dpkg-is-another-process