在CentOS7和CentOS8上卸载已安装的docker并安装特定版本的docker。
卸载已存在版本
首先我们卸载已经安装的版本
yum remove docker-ce docker-ce-cli containerd.io
yum remove docker \
docker-client \
docker-client-latest \
docker-common \
docker-latest \
docker-latest-logrotate \
docker-logrotate \
docker-engine

导入yum源
导入docker官方提供的yum源,如果网络不好使用官网yum源比较慢的同学也可以使用阿里云提供的镜像yum源。
sudo yum install -y yum-utils device-mapper-persistent-data lvm2
sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
大家可以直接复制下面的yum源直接保存到/etc/yum.repo.d/目录下。
下面的这个是阿里云的镜像源版本:
[docker-ce-stable]
name=Docker CE Stable - $basearch
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/$basearch/stable
enabled=1
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
[docker-ce-stable-debuginfo]
name=Docker CE Stable - Debuginfo $basearch
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/debug-$basearch/stable
enabled=0
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
[docker-ce-stable-source]
name=Docker CE Stable - Sources
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/source/stable
enabled=0
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
[docker-ce-edge]
name=Docker CE Edge - $basearch
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/$basearch/edge
enabled=0
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
[docker-ce-edge-debuginfo]
name=Docker CE Edge - Debuginfo $basearch
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/debug-$basearch/edge
enabled=0
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
[docker-ce-edge-source]
name=Docker CE Edge - Sources
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/source/edge
enabled=0
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
[docker-ce-test]
name=Docker CE Test - $basearch
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/$basearch/test
enabled=0
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
[docker-ce-test-debuginfo]
name=Docker CE Test - Debuginfo $basearch
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/debug-$basearch/test
enabled=0
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
[docker-ce-test-source]
name=Docker CE Test - Sources
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/source/test
enabled=0
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
[docker-ce-nightly]
name=Docker CE Nightly - $basearch
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/$basearch/nightly
enabled=0
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
[docker-ce-nightly-debuginfo]
name=Docker CE Nightly - Debuginfo $basearch
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/debug-$basearch/nightly
enabled=0
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
[docker-ce-nightly-source]
name=Docker CE Nightly - Sources
baseurl=https://mirrors.aliyun.com/docker-ce/linux/centos/$releasever/source/nightly
enabled=0
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
下面的这个是清华的镜像源版本:
[docker-ce-stable]
name=Docker CE Stable - $basearch
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/$basearch/stable
enabled=1
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
[docker-ce-stable-debuginfo]
name=Docker CE Stable - Debuginfo $basearch
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/debug-$basearch/stable
enabled=0
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
[docker-ce-stable-source]
name=Docker CE Stable - Sources
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/source/stable
enabled=0
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
[docker-ce-edge]
name=Docker CE Edge - $basearch
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/$basearch/edge
enabled=0
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
[docker-ce-edge-debuginfo]
name=Docker CE Edge - Debuginfo $basearch
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/debug-$basearch/edge
enabled=0
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
[docker-ce-edge-source]
name=Docker CE Edge - Sources
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/source/edge
enabled=0
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
[docker-ce-test]
name=Docker CE Test - $basearch
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/$basearch/test
enabled=0
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
[docker-ce-test-debuginfo]
name=Docker CE Test - Debuginfo $basearch
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/debug-$basearch/test
enabled=0
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
[docker-ce-test-source]
name=Docker CE Test - Sources
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/source/test
enabled=0
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
[docker-ce-nightly]
name=Docker CE Nightly - $basearch
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/$basearch/nightly
enabled=0
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
[docker-ce-nightly-debuginfo]
name=Docker CE Nightly - Debuginfo $basearch
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/debug-$basearch/nightly
enabled=0
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
[docker-ce-nightly-source]
name=Docker CE Nightly - Sources
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/$releasever/source/nightly
enabled=0
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/gpg
安装docker
接着我们从高到低列出yum源中各个版本的docker
yum list docker-ce --showduplicates | sort -r

安装特定版本的命令如下
yum install docker-ce-<VERSION_STRING> docker-ce-cli-<VERSION_STRING> containerd.io
如果需要安装最新版本的话,我们直接这样:
yum install docker-ce docker-ce-cli containerd.io
这里我们安装18.9.0的版本
yum install docker-ce-18.09.0-3.el7 docker-ce-cli-18.09.0-3.el7 containerd.io
Install a specific version by its fully qualified package name, which is the package name (
docker-ce) plus the version string (2nd column) starting at the first colon (:), up to the first hyphen, separated by a hyphen (-). For example,docker-ce-18.09.1.
这里和官网的说明有一点不一样,这里我们需要加上后面的-3.el7,否则检测不到安装包。

更换cgroup驱动
k8s推荐docker的cgroup驱动使用systemd,说是会更稳定,所以这里我们还需要修改一下,同时这里更换docker的镜像源为中科大的镜像源。
## Create /etc/docker directory.
mkdir /etc/docker
# Setup daemon.
cat > /etc/docker/daemon.json <<EOF
{
"exec-opts": ["native.cgroupdriver=systemd"],
"log-driver": "json-file",
"log-opts": {
"max-size": "100m"
},
"storage-driver": "overlay2",
"storage-opts": [
"overlay2.override_kernel_check=true"
],
"registry-mirrors": ["https://docker.mirrors.ustc.edu.cn"]
}
EOF
mkdir -p /etc/systemd/system/docker.service.d
# Restart Docker
systemctl daemon-reload
systemctl restart docker
配置普通用户
默认情况下,普通用户需要使用sudo才能操作docker,我们这里需要进行一些修改。
# 切换到普通用户
su 普通用户名
# 创建docker组
sudo groupadd docker
# 将当前用户加入docker用户组
sudo gpasswd -a ${USER} docker
# 重启docker服务
sudo systemctl daemon-reload
sudo systemctl restart docker
配置内核参数
保险起见,我们还需要配置内核参数确保docker的网络正常
cat >> /etc/sysctl.conf <<EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl -p
reboot
测试
# 启动docker
sudo systemctl start docker
# 最后我们还要设置一下开机启动
sudo systemctl enable docker
# 跑个helloworld看看
sudo docker run hello-world

如果成功运行则说明docker安装成功。