这里环境为ubuntu版本为18.04

使用APT安装docker

# 更新软件源
sudo apt-get update
# 安装所需依赖
sudo apt-get -y install apt-transport-https ca-certificates curl software-properties-common
# 安装 GPG 证书
curl -fsSL http://mirrors.aliyun.com/docker-ce/linux/ubuntu/gpg | sudo apt-key add -
# 新增软件源信息
sudo add-apt-repository "deb [arch=amd64] http://mirrors.aliyun.com/docker-ce/linux/ubuntu $(lsb_release -cs) stable"
# 再次更新软件源
sudo apt-get -y update
# 安装 Docker CE 版
sudo apt-get -y install docker-ce

以上操作安装默认安装的docker版本为latest，如果要指定版本，则先暂时不执行最后的一步，即：sudo apt-get -y install docker-ce （先不执行此步骤）

查看docker版本

sudo apt-cache madison docker-ce

使用该语句查看docker版本列表，结果如下：

root@kubernetes-master:~# apt-cache madison docker-ce
 docker-ce | 5:20.10.6~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:20.10.5~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:20.10.4~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:20.10.3~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:20.10.2~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:20.10.1~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:20.10.0~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.15~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.14~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.13~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.12~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.11~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.10~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.9~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.8~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.7~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.6~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.5~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.4~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.3~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.2~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.1~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:19.03.0~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:18.09.9~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:18.09.8~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:18.09.7~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:18.09.6~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:18.09.5~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:18.09.4~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:18.09.3~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:18.09.2~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:18.09.1~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 5:18.09.0~3-0~ubuntu-bionic | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 18.06.3~ce~3-0~ubuntu | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 18.06.2~ce~3-0~ubuntu | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 18.06.1~ce~3-0~ubuntu | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 18.06.0~ce~3-0~ubuntu | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
 docker-ce | 18.03.1~ce~3-0~ubuntu | http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages

安装指定版本的docker

这是开始执行之前暂定的那一步：sudo apt-get -y install docker-ce
新的拉取语句为：

apt-get install docker-ce=5:19.03.9~3-0~ubuntu-bionic

对比，就是docker-ce后面加了版本号，而版本号直接复制之前查询出的版本列表。
执行结果如下：

root@kubernetes-master:~# apt-get install docker-ce=5:19.03.9~3-0~ubuntu-bionic
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following additional packages will be installed:
  aufs-tools cgroupfs-mount docker-ce-cli docker-scan-plugin
The following NEW packages will be installed:
  aufs-tools cgroupfs-mount docker-ce docker-ce-cli docker-scan-plugin
0 upgraded, 5 newly installed, 0 to remove and 27 not upgraded.
Need to get 22.6 MB/67.9 MB of archives.
After this operation, 295 MB of additional disk space will be used.
Do you want to continue? [Y/n] Y
Get:1 http://mirrors.cloud.aliyuncs.com/ubuntu bionic/universe amd64 aufs-tools amd64 1:4.9+20170918-1ubuntu1 [104 kB]
Get:2 http://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 docker-ce amd64 5:19.03.9~3-0~ubuntu-bionic [22.5 MB]
Get:3 http://mirrors.cloud.aliyuncs.com/ubuntu bionic/universe amd64 cgroupfs-mount all 1.4 [6,320 B]
Fetched 22.6 MB in 2s (9,642 kB/s)                                    
Selecting previously unselected package aufs-tools.
(Reading database ... 111708 files and directories currently installed.)
Preparing to unpack .../aufs-tools_1%3a4.9+20170918-1ubuntu1_amd64.deb ...
Unpacking aufs-tools (1:4.9+20170918-1ubuntu1) ...
Selecting previously unselected package cgroupfs-mount.
Preparing to unpack .../cgroupfs-mount_1.4_all.deb ...

检测安装情况

sudo docker version

或者

sudo docker info

自己记录一下，免得每次在网上找半天