I’ve made a kubernetes cluster on rancher with 1 master and 3 workers. They were all using centos, but it was horribly slow since I was using overlay filesystem with docker. I drained/deleted one worker and changed the OS to RancherOS with overlay2 and my containers are much faster now! So I did it to the other 2 workers as well.
How can I change the OS on the master? Is it as easy as temporarily adding a second master node while doing work on the first one?
Additional info: all nodes are VMs. All worker container persistent data is on a NAS.