阿里云Ubuntu20.4 安装docker

1、打开docker官网关于ubuntu系统的页面：https://docs.docker.com/engine/install/ubuntu/ 按照提示使用 apt 仓库步骤执行（Install using the apt repository）

2、更新Ubuntu的apt源索引

sudo apt-get update

3、安装包允许apt通过HTTPS使用仓库

sudo apt-get install \
    ca-certificates \
    curl \
    gnupg

3、添加Docker官方GPG key

在终端执行以下3条命令：

sudo install -m 0755 -d /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
sudo chmod a+r /etc/apt/keyrings/docker.gpg

4、设置Docker稳定版仓库:

执行以下这条命令：

echo \
  "deb [arch="$(dpkg --print-architecture)" signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu \
  "$(. /etc/os-release && echo "$VERSION_CODENAME")" stable" | \
  sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

5、Install Docker Engine

5.1 更新apt源索引:

sudo apt-get update

5.2  Install Docker Engine, containerd, and Docker Compose.

sudo apt-get install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

6.Verify that the Docker Engine installation is successful by running the hello-world image:

sudo docker run hello-world

7. 或者也可以使用docker命令验证是否安装成功：

 docker --version

8、启动服务并查看信息

sudo service docker start
sudo service docker stop
sudo service docker restart
docker info