操作系统

64位CentOS Linux release 7.2.1511 (Core)

配置好IP：192.168.1.160

修改yum源

目的是提升对docker的下载速度。

1.备份你的原镜像文件，以免出错后可以恢复。

[root@localhost ~]# mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup

2.下载新的CentOS-Base.repo 到/etc/yum.repos.d/

[root@localhost ~]# wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

3.运行yum makecache生成缓存

[root@localhost ~]# yum clean all
[root@localhost ~]# yum makecache

安装Docker

[root@localhost ~]# yum -y install docker-io

要稍等几分钟才能安装好。网速快的话几十秒吧。

启动Docker

[root@localhost ~]# systemctl start docker

发现会报错：

Job for docker.service failed because the control process exited with error code. See "systemctl status docker.service" and "journalctl -xe" for details.

按照提示执行：

[root@localhost ~]# systemctl status docker.service

会有提示信息如下：

● docker.service - Docker Application Container EngineLoaded: loaded (/usr/lib/systemd/system/docker.service; disabled; vendor preset: disabled)Active: failed (Result: exit-code) since 三 2018-05-02 23:34:46 CST; 52s agoDocs: http://docs.docker.comProcess: 14416 ExecStart=/usr/bin/dockerd-current --add-runtime docker-runc=/usr/libexec/docker/docker-runc-current --default-runtime=docker-runc --exec-opt native.cgroupdriver=systemd --userland-proxy-path=/usr/libexec/docker/docker-proxy-current --seccomp-profile=/etc/docker/seccomp.json $OPTIONS $DOCKER_STORAGE_OPTIONS $DOCKER_NETWORK_OPTIONS $ADD_REGISTRY $BLOCK_REGISTRY $INSECURE_REGISTRY $REGISTRIES (code=exited, status=1/FAILURE)Main PID: 14416 (code=exited, status=1/FAILURE)5月 02 23:34:45 localhost.localdomain systemd[1]: Starting Docker Application Container Engine...
5月 02 23:34:45 localhost.localdomain dockerd-current[14416]: time="2018-05-02T23:34:45.527821208+08:00" level=warning msg="could not change group /var/run/...t found"
5月 02 23:34:45 localhost.localdomain dockerd-current[14416]: time="2018-05-02T23:34:45.532650572+08:00" level=info msg="libcontainerd: new containerd proce...: 14421"
5月 02 23:34:46 localhost.localdomain dockerd-current[14416]: time="2018-05-02T23:34:46.539484373+08:00" level=warning msg="overlay2: the backing xfs filesystem is ...
5月 02 23:34:46 localhost.localdomain dockerd-current[14416]: Error starting daemon: SELinux is not supported with the overlay2 graph driver on this kernel....d=false)
5月 02 23:34:46 localhost.localdomain systemd[1]: docker.service: main process exited, code=exited, status=1/FAILURE
5月 02 23:34:46 localhost.localdomain systemd[1]: Failed to start Docker Application Container Engine.
5月 02 23:34:46 localhost.localdomain systemd[1]: Unit docker.service entered failed state.
5月 02 23:34:46 localhost.localdomain systemd[1]: docker.service failed.
Hint: Some lines were ellipsized, use -l to show in full.

红色部分告诉我们此linux的内核中的SELinux不支持 overlay2 graph driver，解决方法有两个，要么启动一个新内核，要么就在docker里禁用selinux，设置--selinux-enabled=false。我们采用第二种方式。

[root@localhost ~]# vi /etc/sysconfig/docker

然后将--selinux-enabled设置成false，保存并退出。

# /etc/sysconfig/docker# Modify these options if you want to change the way the docker daemon runs
OPTIONS='--selinux-enabled=false --log-driver=journald --signature-verification=false'
if [ -z "${DOCKER_CERT_PATH}" ]; thenDOCKER_CERT_PATH=/etc/docker
fi
# ......省略N行

重新启动

[root@localhost ~]# systemctl start docker

查看版本号

[root@localhost ~]# docker -v

Docker version 1.13.1, build 774336d/1.13.1

至此docker启动成功

修改Docker镜像加速器

因为国外的docker镜像访问太慢，所以我们需要修改成阿里云的docker镜像。这样从国内镜像拉取速度会快点。

1．打开阿里云docker仓库地址https://dev.aliyun.com/search.html

2．淘宝账号即可登录，登录后点击自己的管理中心。

3．点击管理中心左侧菜单栏的“镜像加速器”，右边面板会有你的加速地址，面板下面有详细设置步骤。如下图：

[root@localhost ~]# vi /etc/docker/daemon.json

将下面整行字符拷贝进去，保存并退出。

"registry-mirrors": ["https://njrds9qc.mirror.aliyuncs.com"]

刷新daemon

[root@localhost ~]# systemctl daemon-reload

重启docker

[root@localhost ~]# systemctl restart docker

拉取镜像

以hello-world为例

[root@localhost tmp]# docker pull hello-world
Using default tag: latest
Trying to pull repository docker.io/library/hello-world ... 
latest: Pulling from docker.io/library/hello-world
9bb5a5d4561a: Pull complete 
Digest: sha256:f5233545e43561214ca4891fd1157e1c3c563316ed8e237750d59bde73361e77
Status: Downloaded newer image for docker.io/hello-world:latest

表示成功拉取

运行镜像

[root@localhost tmp]# docker run hello-worldHello from Docker!
This message shows that your installation appears to be working correctly.To generate this message, Docker took the following steps:1. The Docker client contacted the Docker daemon.2. The Docker daemon pulled the "hello-world" image from the Docker Hub.(amd64)3. The Docker daemon created a new container from that image which runs theexecutable that produces the output you are currently reading.4. The Docker daemon streamed that output to the Docker client, which sent itto your terminal.To try something more ambitious, you can run an Ubuntu container with:$ docker run -it ubuntu bashShare images, automate workflows, and more with a free Docker ID:https://hub.docker.com/

For more examples and ideas, visit:https://docs.docker.com/engine/userguide/