Install another k3s master

On the new master

Become root.

sudo su

Then update the OS.

apt-get update -y
apt-get upgrade -y

Log back into the new master and become root.

sudo su

Add the following to /boot/cmdline.txt.

cgroup_enable=cpuset cgroup_memory=1 cgroup_enable=memory

Reboot the new master.


On the machine you are using to manage the cluster

Copy the SSH keys into the node (replace NEW-MASTER-IP with the IP address of the new master).

ssh-copy-id pi@NEW-MASTER-IP

Join the new master to the k3s cluster as a master (replace NEW-MASTER-IP with the IP address of the node and CURRENT-MASTER-IP with the IP address of a current master).

k3sup join --ip <NEW-MASTER-IPp> --user pi --server-user pi --server-ip <CURRENT-MASTER-IP> --server

And voila you have added another master to your k3s cluster!

Posted April 9th, 2021