Create swap file on Ubuntu

ubuntu_create_swap.sh

# taken from https://www.linode.com/docs/guides/how-to-increase-swap-space-in-ubuntu/
sudo swapon --show # show if there is any swap area
free -h 
sudo fallocate -l 2G /swapfile # allocate the sw file
sudo chmod 600 /swapfile # only sudo can write
sudo mkswap /swapfile # designate file as swap
sudo swapon /swapfile # activate
sudo swapon --show # show if the file is activated
free -h # show swap
sudo cp /etc/fstab /etc/fstab.bak # backup stab file
sudo vi /etc/fstab # edit fstab
/swapfile       swap            swap    defaults          0     0