Ubuntu 20.04 LTS 安装 Docker

curl -fsSL https://get.docker.com -o get-docker.sh
sudo sh get-docker.sh

sudo apt remove docker docker-engine docker.io containerd runc

sudo apt update

sudo apt install \
  apt-transport-https \
  ca-certificates \
  curl \
  gnupg-agent \
  software-properties-common

  curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -

OK

  sudo apt-key fingerprint 0EBFCD88

pub   rsa4096 2017-02-22 [SCEA]
      9DC8 5822 9FC7 DD38 854A  E2D8 8D81 803C 0EBF CD88
uid           [ unknown] Docker Release (CE deb) <docker@docker.com>
sub   rsa4096 2017-02-22 [S]

sudo add-apt-repository \
 "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
 $(lsb_release -cs) \
 stable"

sudo add-apt-repository \
   "deb [arch=amd64] https://mirrors.aliyun.com/docker-ce/linux/ubuntu \
   $(lsb_release -cs) \
   stable"

sudo apt update

sudo apt install docker-ce docker-ce-cli containerd.io

apt-cache madison docker-ce

docker-ce | 5:19.03.8~3-0~ubuntu-bionic | https://download.docker.com/linux/ubuntu bionic/stable amd64 Packages
docker-ce | 5:19.03.8~3-0~ubuntu-bionic | https://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
docker-ce | 18.06.3~ce~3-0~ubuntu | https://download.docker.com/linux/ubuntu bionic/stable amd64 Packages
docker-ce | 18.06.3~ce~3-0~ubuntu | https://mirrors.aliyun.com/docker-ce/linux/ubuntu bionic/stable amd64 Packages
...

 apt-cache madison docker-ce
docker-ce | 5:19.03.9~3-0~ubuntu-focal | https://mirrors.aliyun.com/docker-ce/linux/ubuntu focal/stable amd64 Packages

sudo apt install docker-ce=<VERSION_STRING> docker-ce-cli=<VERSION_STRING> containerd.io

sudo docker run hello-world

Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
0e03bdcc26d7: Pull complete
Digest: sha256:8e3114318a995a1ee497790535e7b88365222a21771ae7e53687ad76563e8e76
Status: Downloaded newer image for hello-world:latest

Hello 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 the
    executable that produces the output you are currently reading.
 4. The Docker daemon streamed that output to the Docker client, which sent it
    to your terminal.

To try something more ambitious, you can run an Ubuntu container with:
   docker run -it ubuntu bash

Share images, automate workflows, and more with a free Docker ID:
 https://hub.docker.com/

For more examples and ideas, visit:
 https://docs.docker.com/get-started/

sudo usermod -aG docker $USER

sudo systemctl restart docker

sudo mkdir -p /etc/docker
sudo sh -c "echo '
{
  "registry-mirrors": ["https://registry.docker-cn.com"]
}
' > /etc/docker/daemon.json"

# 可以考虑多个镜像
sudo sh -c "echo '
{
  "registry-mirrors": [
    "https://hub-mirror.c.163.com",
    "https://reg-mirror.qiniu.com",
    "https://registry.docker-cn.com"
  ]
}
' > /etc/docker/daemon.json"

# reload生效
systemctl reload docker

# 或者重启docker
systemctl restart docker