Preparing the servers

You will need to prepare your servers for the installation of k3s.

Assign static IPs

For the cluster to work properly, you need to assign static IPs to the servers. You can do so on your router settings.

Swap must be disabled on all servers. Edit the /etc/fstab and comment out the line that contains swap image. It should look like this:

/swap.img      none    swap    sw      0       0

Then reboot the server.

If you haven't yet created an SSH key, you can do so with the following command:

ssh-keygen -t ed25519 -C "your_email@example.com"

You can then copy it to the servers using ssh-copy-id:

ssh-copy-id -i ~/.ssh/id_ed25519.pub lorenzo@<host ip>

lorenzo is the username I use to connect to the servers. You can replace it with your own username.

Because k3sup uses SSH with sudo, you need to allow running sudo without a password. To do this, open the sudoers file with:

sudo visudo

and add this line at the end of the file:

lorenzo ALL=(ALL) NOPASSWD:ALL