Docker: 创建保存镜像

镜像的创建和保存

• 基于现有父镜像开发并commit
• 使用Dockerfile文件创建

一.基于现有父镜像开发并commit

1. pull and start a new container

docker pull ubuntu:18.04
docker run -it ubuntu:18.04 bash

2. deploy app and edit /run.sh

3. exit and commit this container

// docker commit ID SW_NAME:VERSION
// example:
root@13336c183077:/# exit
exit
bear@k40 ~% docker commit 13336c183077 ubuntu.18.04:v1

4. run the new container by run.sh

docker run ubuntu.18.04:v1 /run.sh

二.使用Dockerfile文件创建

1. touch a new Dockerfile and edit:

FROM nginx
RUN echo 'I'm nginx' > /usr/share/nginx/html/index.html

• FROM: IMAGE, base 父镜像
• RUN：["可执行文件", "参数1", "参数2"], like RUN ["./test.php", "dev", "offline"] == RUN ./test.php dev offline
  注意：

FROM centos
RUN yum install wget
RUN wget -O redis.tar.gz "http://download.redis.io/releases/redis-5.0.3.tar.gz"
RUN tar -xvf redis.tar.gz
以上执行会创建 3 层镜像。可简化为以下格式：
FROM centos
RUN yum install wget \
    && wget -O redis.tar.gz "http://download.redis.io/releases/redis-5.0.3.tar.gz" \
    && tar -xvf redis.tar.gz

2. build new image

当前目录.上下文路径创建镜像：

docker build -t myimage:v1 .