Step 1 – Checking the System for Swap Information
Before we begin, we can check if the system already has some swap space available. It is possible to have multiple swap-files or swap partitions, but generally one should be enough.
We can see if the system has any configured swap by typing:
sudo swapon
Step2 – Creating a Swap File
In Our example we create 4G for /swap.img
sudo fallocate -l /swap.img
Step 3 – Enabling the Swap File
First we give correct permissions for swap
sudo chmod /swap.img
First we format the swap.ing
sudo mkswap /swap.img
Now we turn the swap on
sudo swapon /swap.img
Step 4 – Let´s make permanent changes to our swap-file
Making a backup of /etc/fstab file
sudo cp /etc/fstab /etc/fstab.bak
Adding our swap.img to fstab
echo '/swap.img none swap sw 0 0' sudo tee -a /etc/fstab'