Adding a swap file to small VMs

Low Ram VM’s will struggle with loading the epel repo when installing Kloxo. The solution is to add a swap file.

First check the existing memory with

sudo free -m

In this case my small AWS Lightsail instance has zero swap space

              total        used        free      shared  buff/cache   available
Mem:           913          520         137          15         480         393
Swap:             0           0          0

For yum to run correctly we need to add a swap file. In this case 4GB should be sufficient.

sudo dd if=/dev/zero of=/swap count=4096 bs=1MiB

Then set its permission

sudo chmod 600 /swap

and format it as a swap file

sudo mkswap /swap

Then activate the swap

sudo swapon /swap

Edit fstab so the swap will mount after a reboot

sudo echo "/swap swap swap sw 0 0" >> /etc/fstab

Confirm the swap file is setup

sudo swapon -s

Filename            Type            Size            Used            Priority
/swap               file            4194300         484096          -2

Test the free memory, it should show available swap memory

sudo free -m

               total        used        free      shared  buff/cache   available
Mem:             913         520         137          15         480         393
Swap:           4095         472        3623