利用dockerfile封装centos7容器

• 1.编写 dockerfile 用于封装一个新的镜像

cat > /opt/dockerfile-centos7.yml <<EOF
FROM centos:7
MAINTAINER sqlfans "78667417@qq.com"

ENV TZ Asia/Shanghai
RUN yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

RUN yum install -y -q --nogpgcheck initscripts openssh-clients
RUN yum install -y -q wget curl net-tools

#.安装ansible
# RUN yum install -y -q epel-release
# RUN yum install -y -q ansible

EXPOSE 23245
EOF

• 2.使用 docker build 构建基础镜像，耗时约 00:01:43，镜像大小约 731 MB

time docker build -f /opt/dockerfile-centos7.yml -t centos7:7 .
docker images | grep centos

• 3.利用新的镜像启动centos7容器，并将ssh端口映射为23245

docker run -it -d -p 23245:23245 --name centos7 centos7:7 /bin/bash
docker ps -a | grep centos

• 4.测试一下新的centos容器

docker exec -it centos7 /bin/bash
> ip a
> netstat -lnpt

• 5.测试ok，将新的容器导出，日后 load -i xxx.tar 就可以导入镜像

docker save -o /opt/centos7.2024.tar centos7:7

• x.清理痕迹

docker stop $(docker ps -a | grep centos | awk '{print $1}')
docker rm $(docker ps -a | grep centos | awk '{print $1}')
docker rmi -f $(docker images -qf dangling=true)
docker rmi -f $(docker images | grep centos | awk '{print $3}')