docker.io/ubuntu:20.04

sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<'EOF'
{
  "registry-mirrors": ["https://registry.cn-global.starbucket.com.cn"]
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker

sudo mkdir -p /etc/containerd/certs.d/docker.io
sudo tee /etc/containerd/certs.d/docker.io/hosts.toml <<'EOF'
server = "https://docker.io"

[host."https://registry.cn-global.starbucket.com.cn"]
  capabilities = ["pull", "resolve"]
EOF
sudo mkdir -p /etc/containerd
if [ ! -f /etc/containerd/config.toml ]; then
  sudo containerd config default | sudo tee /etc/containerd/config.toml >/dev/null
fi
sudo sed -i 's#config_path = ""#config_path = "/etc/containerd/certs.d"#' /etc/containerd/config.toml
sudo systemctl restart containerd