Linux Centos7.8 安装docker、docker-compose

记录一下Centos7.8安装dockers。

查看Linux系统信息

cat /etc/redhat-release

一、首先更换yum源

CentOS 7 默认的 YUM 源是 CentOS 官方提供的，但是由于地理位置、网络等问题，可能
会导致使用 YUM 安装软件时速度非常慢。所以更换 CentOS 默认的 YUM 源为阿里云或者其他速度更快的源，我使用的是阿里的YUM源。

1. 备份当前的yum源配置文件

sudo mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup

 2. 下载阿里云的CentOS yum源配置文件

sudo curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

 
 3. 清除yum缓存并生成新的缓存

sudo yum clean all

sudo yum makecache

显示【元数据缓存已建立】即为安装成功。

二、docker安装

1、下载docker-ce的yum源

sudo wget -O /etc/yum.repos.d/docker-ce.repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

2、安装Docker

sudo yum -y install docker-ce

中间会有一小段安装过程，稍等一下，提示【完毕！】即为安装成功。

3、启动docker

（1）启动docker服务

# 启动docker服务
systemctl start docker

停止docker服务命令，后面可能会用到

# 停止docker服务
systemctl stop docker  

如果停止失败，提示
  
那么执行即可

systemctl stop docker.socket

重启docker服务

# 重启docker服务
systemctl restart docker  

（2）配置镜像加速

docker官方镜像仓库网速较差，我们需要设置国内镜像服务：

参考阿里云的镜像加速文档：https://cr.console.aliyun.com/cn-hangzhou/instances/mirrors

a./etc/docker文件夹不存在则创建

sudo mkdir -p /etc/docker

b.执行如下命令，会在/etc/docker中生成一个daemon.json文件

# 生成daemon.json文件
sudo tee /etc/docker/daemon.json <<-'EOF'
{
"registry-mirrors": ["https://seu8x20p.mirror.aliyuncs.com"]
}
EOF

c.加载daemon

# 加载daemon 
sudo systemctl daemon-reload

此处一定要加载，否则会无效或报  

d. 重启docker服务

 sudo systemctl restart docker

（3）配置docker 允许远程连接    

修改docker.service文件，进入目录 /usr/lib/systemd/system/docker.service

 ExecStart后面增加 -H tcp://0.0.0.0:2375

[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network-online.target docker.socket firewalld.service containerd.service time-set.target
Wants=network-online.target containerd.service
Requires=docker.socket

[Service]
Type=notify
# the default is not to use systemd for cgroups because the delegate issues still
# exists and systemd currently does not support the cgroup feature set required
# for containers run by docker
ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock -H tcp://0.0.0.0:2375
ExecReload=/bin/kill -s HUP $MAINPID
TimeoutStartSec=0
RestartSec=2
Restart=always

# Note that StartLimit* options were moved from "Service" to "Unit" in systemd 229.
# Both the old, and new location are accepted by systemd 229 and up, so using the old location
# to make them work for either version of systemd.
StartLimitBurst=3

# Note that StartLimitInterval was renamed to StartLimitIntervalSec in systemd 230.
# Both the old, and new name are accepted by systemd 230 and up, so using the old name to make
# this option work for either version of systemd.
StartLimitInterval=60s

# Having non-zero Limit*s causes performance problems due to accounting overhead
# in the kernel. We recommend using cgroups to do container-local accounting.
LimitNPROC=infinity
LimitCORE=infinity
# Older systemd versions default to a LimitNOFILE of 1024:1024, which is insufficient for many
# applications including dockerd itself and will be inherited. Raise the hard limit, while
# preserving the soft limit for select(2).
LimitNOFILE=1024:524288

# Comment TasksMax if your systemd version does not support it.
# Only systemd 226 and above support this option.
TasksMax=infinity

# set delegate yes so that systemd does not reset the cgroups of docker containers
Delegate=yes

# kill only the docker process, not all processes in the cgroup
KillMode=process
OOMScoreAdjust=-500

[Install]
WantedBy=multi-user.target

（4）重启docker服务

# 重启docker服务
sudo systemctl restart docker

（5）配置docker国内镜像源           

编辑/etc/docker/daemon.json

{
  "registry-mirrors": [
  	"https://docker.m.daocloud.io",
	"https://dockerproxy.com",
	"https://docker.mirrors.ustc.edu.cn",
	"https://docker.nju.edu.cn"
  ]
}

（6）重启 Docker 服务

(此处也一定要加载damon-reload)

sudo systemctl daemon-reload
sudo systemctl restart docker

至此结束，使用idea的docker插件测试一下

如果外部不能访问，先查看防火墙的状态

sudo firewall-cmd --state

# 或者
systemctl status firewalld

防火墙正在运行，那么查看防火墙是否开启了指定端口

firewall-cmd --zone=public --query-port=2375/tcp

未开放2375端口，开放一下

# 开放
firewall-cmd --zone=public --add-port=2375/tcp --permanent
# 限制
firewall-cmd --zone=public --remove-port=2375/tcp --permanent

重新载入一下防火墙设置，使设置生效       

firewall-cmd --reload

大功告成！！！

下一篇记录如何安装docker-compose，http://t.csdnimg.cn/hsSDJ