Docker Overview
- Docker:https://www.docker.com/
- Docker社が開発するOSSのコンテナ型仮想化ソフトウェア
- ハイパーバイザー型の仮想化と比較して、少ないリソースで効率よくアプリケーションを実行できる
- Docker = Docker Engine + Docker Hub
- Docker Hub: https://registry.hub.docker.com/
Docker Command Sample
Show docker information
core@localhost ~ $ docker info
Containers: 1
Images: 5
Storage Driver: overlay
Backing Filesystem: extfs
Execution Driver: native-0.2
Kernel Version: 4.0.3
Operating System: CoreOS 681.0.0
CPUs: 1
Total Memory: 493.9 MiB
Name: localhost
ID: R6ZV:YW52:C6GE:GUD3:QSTR:LXFV:LBCH:ZGSK:YQN6:EWDV:UORV:UCCJ
Download docker images and Show downloaded images
- Download docker images
- docker pull [イメージ名]:[タグ名]
- [イメージ名]：Docker Hub から好みのイメージを選択
- [タグ名]：特に指定がなければ、latestを指定
- docker pull [イメージ名]:[タグ名]
core@localhost ~ $ docker pull ubuntu:latest
latest: Pulling from ubuntu
e118faab2e16: Pull complete
7e2c5c55ef2c: Pull complete
e04c66a223c4: Pull complete
fa81ed084842: Already exists
ubuntu:latest: The image you are pulling has been verified. Important: image verification is a tech preview feature and should not be relied on to provide security.
Digest: sha256:738edd684282277c07f23277718e43562daf2ee210f7aca9a13fae65f0159ddd
Status: Downloaded newer image for ubuntu:latest
- Show docker images
core@localhost ~ $ docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
ubuntu latest fa81ed084842 5 days ago 188.3 MB
alpine latest 8697b6cc1f48 8 days ago 5.238 MB
Create docker container from docker images
- Create docker container from images
core@localhost ~ $ docker run -it --name uTest ubuntu /bin/bash
root@8828b2759963:/# cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.04
DISTRIB_CODENAME=trusty
DISTRIB_DESCRIPTION="Ubuntu 14.04.2 LTS"
root@8828b2759963:/#
- Show docker all containers
- docker ps [-a]: [-a] Optionをつけると停止中のコンテナも表示
core@localhost ~ $ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
8828b2759963 ubuntu:latest "/bin/bash" 9 minutes ago Exited (127) 5 seconds ago uTest
Create docker images from docker container
- Install nginx in docker container
core@localhost ~ $ docker start -a uTest
root@8828b2759963:/# cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.04
DISTRIB_CODENAME=trusty
DISTRIB_DESCRIPTION="Ubuntu 14.04.2 LTS"
root@8828b2759963:/# apt-get install nginx
Reading package lists... Done
Building dependency tree
Reading state information... Done
....
Setting up nginx-common (1.4.6-1ubuntu3) ...
Processing triggers for ureadahead (0.100.0-16) ...
Setting up nginx-core (1.4.6-1ubuntu3) ...
invoke-rc.d: policy-rc.d denied execution of start.
Setting up nginx (1.4.6-1ubuntu3) ...
Processing triggers for libc-bin (2.19-0ubuntu6.6) ...
Processing triggers for sgml-base (1.26+nmu4ubuntu1) ...
- Create docker images from its container
- docker commit [コンテナー名]|[コンテナーID] [[ユーザー名]/][イメージ名]
core@localhost ~ $ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
8828b2759963 ubuntu:latest "/bin/bash" 23 minutes ago Exited (127) 41 seconds ago uTest
core@localhost ~ $ docker commit uTest daicho/ubuntu-nginx
63a2eb92b14d7ad8183aaed48360635b04d1f0b51d6644790ba706a9a6138229
core@localhost ~ $ docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
daicho/ubuntu-nginx latest 63a2eb92b14d 8 seconds ago 206.4 MB
ubuntu latest fa81ed084842 5 days ago 188.3 MB
alpine latest 8697b6cc1f48 8 days ago 5.238 MB
Run docker container on Background
- Run nginx in docker container on Background
core@localhost ~ $ docker run -d -p 80:80 --name nginx1 daicho/ubuntu-nginx /usr/sbin/nginx -g 'daemon off;' -c /etc/nginx/nginx.conf
63998668d76a25e644f5589265971fb484fe7ce65a2f2e0d8a3040985be72870
- Check status of docker container and nginx
core@localhost ~ $ docker run -d -p 80:80 --name nginx1 daicho/ubuntu-nginx /usr/sbin/nginx -g 'daemon off;' -c /etc/nginx/nginx.conf
63998668d76a25e644f5589265971fb484fe7ce65a2f2e0d8a3040985be72870
core@localhost ~ $ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
63998668d76a daicho/ubuntu-nginx:latest "/usr/sbin/nginx -g 2 minutes ago Up 2 minutes 0.0.0.0:80->80/tcp nginx1
core@localhost ~ $ curl localhost:80
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
- Stop docker container
core@localhost ~ $ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
63998668d76a daicho/ubuntu-nginx:latest "/usr/sbin/nginx -g 3 minutes ago Up 3 minutes 0.0.0.0:80->80/tcp nginx1
core@localhost ~ $ docker stop nginx1
nginx1
core@localhost ~ $ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
Remove docker container and downloaded images
- Remove docker container
core@localhost ~ $ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
63998668d76a daicho/ubuntu-nginx:latest "/usr/sbin/nginx -g 5 minutes ago Exited (0) About a minute ago nginx1
core@localhost ~ $ docker rm nginx1
nginx1
core@localhost ~ $ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
- Remove docker images
core@localhost ~ $ docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
daicho/ubuntu-nginx latest 63a2eb92b14d 15 minutes ago 206.4 MB
ubuntu latest fa81ed084842 5 days ago 188.3 MB
alpine latest 8697b6cc1f48 8 days ago 5.238 MB
core@localhost ~ $ docker rmi daicho/ubuntu-nginx
Untagged: daicho/ubuntu-nginx:latest
Deleted: 63a2eb92b14d7ad8183aaed48360635b04d1f0b51d6644790ba706a9a6138229
core@localhost ~ $ docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
ubuntu latest fa81ed084842 5 days ago 188.3 MB
alpine latest 8697b6cc1f48 8 days ago 5.238 MB
core@localhost ~ $