Đầu tiên các bạn cài đặt pass root cho hệ thống 

#!/bin/bash

# Enable ssh password authentication
echo "Enable ssh password authentication"
sed -i 's/^PasswordAuthentication no/PasswordAuthentication yes/' /etc/ssh/sshd_config
sed -i 's/.*PermitRootLogin.*/PermitRootLogin yes/' /etc/ssh/sshd_config
systemctl restart ssh

# Set Root password
echo "Set root password"
echo -e "admin\nadmin" | passwd root >/dev/null 2>&1

Tiếp đến các bạn thực hiện các bước cài đặt docker. 

# Add Docker's official GPG key:
sudo apt-get update
sudo apt-get install ca-certificates curl
sudo install -m 0755 -d /etc/apt/keyrings
sudo curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc
sudo chmod a+r /etc/apt/keyrings/docker.asc

# Add the repository to Apt sources:
echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu \
  $(. /etc/os-release && echo "${UBUNTU_CODENAME:-$VERSION_CODENAME}") stable" | \
  sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

sudo apt-get update

#Install the Docker packages.
sudo apt-get install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

#Verify that the installation is successful by running the hello-world image:
sudo docker run hello-world