Prepare VPS for docker / docker-compose | Ubuntu 16.04 minimal server (256mb ram)

fresh_vps.sh

#! /bin/bash                                                                    
                                                                                
# First add a new sudo user to system                                           
# sudo adduser xx sudo                                                          
                                                                                
# Second change ssh login to key only                                           
# https://www.digitalocean.com/community/tutorials/how-to-set-up-ssh-keys--2    
                                                                                
# And then run this file                                                        
                                                                                
# Add 1G swapfile as root                                                          
sudo -i                                                                         
fallocate -l 1G /swapfile                                                       
chmod 600 /swapfile                                                             
mkswap /swapfile                                                                
swapon /swapfile                                                                
echo "/swapfile none swap sw 0 0" >> /etc/fstab                                 
echo "vm.vfs_cache_pressure = 50" >> /etc/sysctl.conf                           
exit                                                                            
                                                                                
# setup ufw firewall                                                            
sudo ufw default deny incoming && ufw default allow outgoing                    
sudo ufw allow ssh && ufw allow 80/tcp && ufw allow 443/tcp
sudo nano /etc/default/ufw
# Change:
# DEFAULT_FORWARD_POLICY="DROP"
# to
# DEFAULT_FORWARD_POLICY="ACCEPT"
sudo ufw enable                                                                 
                                                                                
# install docker                                                                
sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D
echo "deb https://apt.dockerproject.org/repo ubuntu-xenial main" | sudo tee /etc/apt/sources.list.d/docker.list
sudo apt-get update && apt-cache policy docker-engine                           
sudo apt-get install -y docker-engine                                           
sudo usermod -aG docker $(whoami)                                               
                                                                                
# install docker-compose                                                        
sudo apt-get -y install python-pip && pip install docker-compose

# reboot the system

You should include docker exception to firewall if your container is accessible through port forwarding.