Day 10 Kubernetes 前哨戰-Docker 安裝與基礎操作

本日重點與方向 (TAG): Docker Container、Container
今天將會介紹使用 Bare Metal 進行 Docker 環境的部署，並對於日後的 Kubernetes 叢集竟進行預先搭建使用，基本上就是安裝筆記居多，還有一些 Image 操作的相關知識(姿勢)，詳細的操作還是去看看猴子也都會的一堆農場文吧。

本次使用設備資訊

Network Switch

• 數量: 1
• 型號: D-Link 1210-28 (L2 Switch)

Bare Metal

• 數量: 3
• Ubuntu: 16.04 / 18.04
• Docker Version: 19.03
• CPU: E3-1230_v3
• RAM: 16GB
• Disk: 120 GB (SSD)
• Network: 1Gbps

Docker 安裝

apt-get update
apt-get install -y apt-transport-https \
   ca-certificates \
   curl \
   gnupg-agent \
   software-properties-common
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | apt-key add -
add-apt-repository \
"deb [arch=amd64] https://download.docker.com/linux/ubuntu \
$(lsb_release -cs) \
stable"
apt-get update
apt-get install -y docker-ce docker-ce-cli containerd.io
service docker start

Docker 環境驗證

root@zhengsheng-server-1:~# docker --version
Docker version 19.03.12, build 48a66213fe

Docker 基礎指令功能

Container Image 相關

Image 搜尋

• 多用於查找可用的基底環境使用，或是 Dockerfile 需求。

root@zhengsheng-server-1:~# docker search ubuntu
NAME                                                      DESCRIPTION                                     STARS               OFFICIAL            AUTOMATED
ubuntu                                                    Ubuntu is a Debian-based Linux operating sys…   11303               [OK]           

Image 提取 (Docker Hub)

• 將 Docker Hub 上面的 Image 下載到本機端

root@zhengsheng-server-1:~# docker pull ubuntu:16.04
16.04: Pulling from library/ubuntu
8e097b52bfb8: Pull complete 
a613a9b4553c: Pull complete 
acc000f01536: Pull complete 
73eef93b7466: Pull complete 
Digest: sha256:3dd44f7ca10f07f86add9d0dc611998a1641f501833692a2651c96defe8db940
Status: Downloaded newer image for ubuntu:16.04
docker.io/library/ubuntu:16.04

Image 編譯

範例 Dockerfile

FROM busybox

CMD ["echo" ,"'This is my first comtainer image build container !'"]

編譯指令

這邊 Container Image 的編譯會基於你先前的編譯去做修改，要用每次都全部重新編譯的話，要使用非快取的指令方式。

• 簡易快速編譯方式

root@zhengsheng-server-1:~/test# docker build -t test-image .
Sending build context to Docker daemon  3.072kB
Step 1/2 : FROM busybox
 ---> 018c9d7b792b
Step 2/2 : CMD ["echo" ,"'This is my first comtainer image build container !'"]
 ---> Running in bddf96992e35
Removing intermediate container bddf96992e35
 ---> 6ed02ff90585
Successfully built 6ed02ff90585
Successfully tagged test-image:latest

• 生成 Image Tag 編譯的方式(設定 Image 版本號)

root@zhengsheng-server-1:~/test# docker build -t test-image:v0.0.1 .
Sending build context to Docker daemon  2.906MB
Step 1/2 : FROM busybox
 ---> 018c9d7b792b
Step 2/2 : CMD ["echo" ,"'This is my first comtainer image build container !'"]
 ---> Using cache
 ---> aa122484a764
Successfully built aa122484a764
Successfully tagged test-image:v0.0.1

• 無快取編譯方式

root@zhengsheng-server-1:~/test# docker build --no-cache -t test-image .
Sending build context to Docker daemon  4.608kB
Step 1/2 : FROM busybox
 ---> 018c9d7b792b
Step 2/2 : CMD ["echo" ,"'This is my first comtainer image build container !'"]
 ---> Running in cc1b3d5f7969
Removing intermediate container cc1b3d5f7969
 ---> aa122484a764
Successfully built aa122484a764
Successfully tagged test-image:latest

測試指令

root@zhengsheng-server-1:~/test# docker run -ti test-image 
'This is my first comtainer image build container !'

Image 匯出/引入

匯出 Image

• 查找 Image 名稱或是 ID 後續進行匯出時取用，這邊的版本號也會作為匯出的參考值。

root@zhengsheng-server-1:~/test# docker images
REPOSITORY                             TAG                 IMAGE ID            CREATED             SIZE
test-image                             latest              aa122484a764        11 minutes ago      1.22MB
test-image                             v0.0.1              aa122484a764        11 minutes ago      1.22MB

• 匯出指令

沒指定版本號的話，一般來說會基於 latest 版本去做封裝。

root@zhengsheng-server-1:~/test# docker save -o test-image.tar.gz test-image
root@zhengsheng-server-1:~/test# docker save -o test-image_v0.0.1.tar.gz test-image:v0.0.1
root@zhengsheng-server-1:~/test# ls
Dockerfile  test-image.tar.gz  test-image_v0.0.1.tar.gz

匯入 Image

root@sdn-k8s-b2-1:/home/ubuntu# docker load -i test-image.tar.gz 
Loaded image: test-image:latest
root@sdn-k8s-b2-1:/home/ubuntu# docker load -i test-image_v0.0.1.tar.gz 
Loaded image: test-image:v0.0.1
root@sdn-k8s-b2-1:/home/ubuntu# docker images
REPOSITORY                             TAG                 IMAGE ID            CREATED             SIZE
test-image                             latest              aa122484a764        24 minutes ago      1.22MB
test-image                             v0.0.1              aa122484a764        24 minutes ago      1.22MB

Image 刪除

root@sdn-k8s-b2-1:/home/ubuntu# docker rmi test-image
Untagged: test-image:latest
root@sdn-k8s-b2-1:/home/ubuntu# docker rmi test-image:v0.0.1
Untagged: test-image:v0.0.1
Deleted: sha256:aa122484a764f0cda0703ae3980881bc0819c21c4411599653c74f0f0380fa16
Deleted: sha256:514c3a3e64d4ebf15f482c9e8909d130bcd53bcc452f0225b0a04744de7b8c43