docker 02

Posted 2020-10-27

一、基于centos:latest创建新的镜像，新镜像已经配置好了yum并且安装了net-tools
１、基于centos起动容器
[[email protected] docker_images]# docker run -it centos bash
2、在容器中配置yum，并安装net-tools
[[email protected] /]# rm -f /etc/yum.repos.d/*
[[email protected] /]# vi /etc/yum.repos.d/server.repo
[server]
name=server
baseurl=ftp://192.168.4.254/rhel7.2
enabled=1
gpgcheck=0
[[email protected] /]# yum install -y net-tools
3、将容器commit成为镜像
[[email protected] docker_images]# docker commit 798d29ec0d54 mycentos
[[email protected] docker_images]# docker images
4、使用新镜像起动容器，测试yum和net-tools是否可用
[[email protected] docker_images]# docker run -it mycentos bash
[[email protected] /]# yum repolist
[[email protected] /]# ifconfig
二、通过dockerfile生成镜像
１、创建工作目录
[[email protected] docker_images]# mkdir -p ~/mydocker/build1
[[email protected] docker_images]# cd ~/mydocker/build1
2、编写Dockerfile
[[email protected] build1]# vim Dockerfile
FROM centos:latest
CMD ["/bin/echo", "Hello tedu"]
3、生成镜像
[[email protected] build1]# docker build -t mytest:latest .
4、测试
[[email protected] build1]# docker run -it mytest
[[email protected] build1]# docker ps
注意：容器输入hello tedu后就退出了，因为它的使命已经结束

三、生成镜像
１、创建工作目录
[[email protected] build1]# mkdir ~/mydocker/build2
[[email protected] build1]# cd ~/mydocker/build2
2、编写Dockerfile
[[email protected] build2]# vim Dockerfile
FROM mycentos:latest
MAINTAINER zzg [email protected]
WORKDIR /var/www/html
ADD mytest.sh /root/mytest.sh
RUN yum install -y httpd
RUN yum install -y php
RUN yum install -y php-mysql
EXPOSE 80
CMD ["httpd", "-DFOREGROUND"]
3、生成镜像
[[email protected] build2]# echo ‘pwd‘ > mytest.sh
[[email protected] build2]# docker build -t centos:http .
4、验证
[[email protected] build2]# docker run -P -itd centos:http

四、生成镜像的建议
１、每个容器只运行一个进程
２、不要假定你的容器可以一直处于运行状态，它们只是临时的，很有可能被停止
３、使用.dockerignore文件排除不想加入到镜像中的文件
４、使用官方提供的镜像，而不是自己头０制作
５、尽量减少镜像的层次

基于镜像起动多个容器
[[email protected] build3]# for i in {1..5}; do docker run -P -h web$i --name web$i -itd centos:apache; done

练习：
基于centos，生成mysql镜像
[[email protected] mydocker]# cp -r build3 build4
[[email protected] mydocker]# cd build4
[[email protected] build4]# vim Dockerfile
FROM mycentos:latest
MAINTAINER zzg [email protected]
RUN yum install -y mariadb-server; mysql_install_db; chown -R mysql:mysql /var/lib/mysql
EXPOSE 3306
CMD ["mysqld_safe"]
[[email protected] build4]# docker build -t centos:mysql .
[[email protected] build4]# docker run -P -itd centos:mysql
[[email protected] build4]# docker exec -it f1ee bash
[[email protected] /]# mysql -uroot

将vh01设置成为docker仓库服务器
１、下载仓库镜像
[[email protected] docker_images]# docker load < registry.tar
２、修改docker服务，可以使用本地仓库
[[email protected] docker_images]# vim /usr/lib/systemd/system/docker.service
ExecStart=/usr/bin/dockerd --insecure-registry=192.168.4.1:5000
[[email protected] docker_images]# systemctl daemon-reload
[[email protected] docker_images]# systemctl restart docker
3、导入的registry镜像没有名称，为其添加名字
[[email protected] docker_images]# docker tag c9bd19d022f6 registry
４、后台起动registry
[[email protected] docker_images]# docker run -id -p 5000:5000 registry
5、镜像名称格式是：仓库名/镜像名 才能上传
[[email protected] docker_images]# docker tag centos:apache 192.168.4.1:5000/centos:apache
[[email protected] docker_images]# docker images
6、上传镜像到仓库
[[email protected] docker_images]# docker push 192.168.4.1:5000/centos:apache

准备虚拟机vh02，使期可以使用docker仓库
1、初始化vh02
vh02.tedu.cn 192.168.4.2/24 selinux firewalld yum
2、在vh02上安装docker，并设置其可以使用vh01提供的仓库
[[email protected] docker]# scp rpm 192.168.4.2:/root
[[email protected] ~]# yum install -y rpm
[[email protected] ~]# vim /usr/lib/systemd/system/docker.service
ExecStart=/usr/bin/dockerd --insecure-registry=192.168.4.1:5000
[[email protected] ~]# systemctl daemon-reload
[[email protected] ~]# systemctl start docker
[[email protected] ~]# systemctl enable docker
3、下载192.168.4.1的镜像
[[email protected] ~]# docker pull 192.168.4.1:5000/centos:apache
4、验证
[[email protected] ~]# docker run -id 192.168.4.1:5000/centos:apache
[[email protected] ~]# docker ps

持久化存储
１、不要在容器里存放重要数据，应该将数据存储在宿主机上
[[email protected] ~]# docker run -idt -P --name web1 -v /webroot/web1:/var/www/html 192.168.4.1:5000/centos:apache
[[email protected] ~]# echo ‘<h1>my test</h1>‘ > /webroot/web1/index.html
2、查看容器的端口号
[[email protected] ~]# docker ps
3、访问容器的http服务

配置存储服务器，vh01和vh02上的容器存储的数据将存放在vh03上
１、准备vh03
vh03.tedu.cn 192.168.4.3 selinux firewalld yum
2、创建nfs共享目录
[[email protected] ~]# mkdir -m 777 /nfsroot
3、安装nfs服务
[[email protected] ~]# yum install -y nfs-utils
4、配置共享声明
[[email protected] ~]# vim /etc/exports
/nfsroot 192.168.4.*(rw,sync)
5、起动服务
[[email protected] ~]# systemctl restart nfs-server.service
6、查看输出列表
[[email protected] ~]# showmount -e 192.168.4.3
7、在vh01和vh02上将共享目录永久挂载到/dockdir
[[email protected] docker]# mkdir /dockdir
[[email protected] docker]# tail -1 /etc/fstab
192.168.4.3:/nfsroot /dockdir nfs defaults 0 0
[[email protected] docker]# mount -a
8、起动容器，将容器的卷对应到nfs共享中
[[email protected] docker]# docker run -idt -P -v /dockdir/vh01/web1:/var/www/html 192.168.4.1:5000/centos:apache
[[email protected] ~]# docker run -idt -P -v /dockdir/vh02/web1:/var/www/html 192.168.4.1:5000/centos:apache

创建自定义网络
１、创建名为test02的网络，ip地址使用172.30.0.0/24

docker network create --subnet=172.30.0.0/16 test02

2、起动容器，指定连接的网桥是test02

docker run --network=test02 -idt 192.168.4.1:5000/centos:apache

docker inspect <容器id>