Become root.
sudo su
Then update the OS.
apt-get update -y apt-get upgrade -y reboot
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.
reboot
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