Ubuntu Docker 安装
在 Ubuntu 上用官方 apt 仓库安装 Docker Engine，并做非 root 与开机自启配置。
Key Points用 Docker 官方 apt 仓库安装，不要用 Ubuntu 自带的 docker.io 包（版本旧）；装完把用户加进 docker 组。
卸载旧版本
Bash
sudo apt-get remove docker docker-engine docker.io containerd runc配置官方仓库
Bash
sudo apt-get update
sudo apt-get install -y ca-certificates curl gnupg
# 添加 GPG 密钥
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
# 添加仓库
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安装
Bash
sudo apt-get update
sudo apt-get install -y docker-ce docker-ce-cli containerd.io \
docker-buildx-plugin docker-compose-plugin验证与配置
Bash
sudo systemctl enable --now docker
sudo docker run --rm hello-world
# 免 sudo（重新登录后生效）
sudo usermod -aG docker $USERBeing in the docker group is equivalent to root: members can mount the host filesystem. Be careful on shared machines, or use rootless mode.
卸载旧版本
Bash
sudo apt-get remove docker docker-engine docker.io containerd runc配置官方仓库
Bash
sudo apt-get update
sudo apt-get install -y ca-certificates curl gnupg
# 添加 GPG 密钥
sudo install -m 0755 -d /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg \
| sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
sudo chmod a+r /etc/apt/keyrings/docker.gpg
# 添加仓库
echo "deb [arch=$(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安装
Bash
sudo apt-get update
sudo apt-get install -y docker-ce docker-ce-cli containerd.io \
docker-buildx-plugin docker-compose-plugin验证与配置
Bash
sudo systemctl enable --now docker
sudo docker run --rm hello-world
# 免 sudo（重新登录后生效）
sudo usermod -aG docker $USER加入 docker 组等价于给了 root 权限——组内成员可以直接挂载宿主根目录。多人共用的机器上要谨慎，或者改用 rootless 模式。