Clustering with MicroK8s

Note: Each node on a MicroK8s cluster requires its own environment to work in, whether that is a separate VM or container on a single machine or a different machine on the same network.

Adding a node

To create a cluster out of two or more already-running MicroK8s instances, use the microk8s add-node command. The MicroK8s instance on which this command is run will be the master of the cluster and will host the Kubernetes control plane:

microk8s add-node

This will return some joining instructions, such as:

Join node with:
microk8s join ip-172-31-20-243:25000/DDOkUupkmaBezNnMheTBqFYHLWINGDbf

If the node you are adding is not reachable through the default
interface you can use one of the following:

microk8s join 10.1.84.0:25000/DDOkUupkmaBezNnMheTBqFYHLWINGDbf
microk8s join 10.22.254.77:25000/DDOkUupkmaBezNnMheTBqFYHLWINGDbf

The add-node command prints a microk8s join command which should
be executed on the MicroK8s instance that you wish to join to the
cluster (NOT THE NODE YOU RAN add-node FROM)
:

microk8s join ip-172-31-20-243:25000/DDOkUupkmaBezNnMheTBqFYHLWINGDbf

Joining a node to the cluster should only take a few seconds. Afterwards
you should be able to see the node has joined:

microk8s kubectl get no
NAME               STATUS   ROLES    AGE   VERSION
10.22.254.79       Ready    <none>   27s   v1.15.3
ip-172-31-20-243   Ready    <none>   53s   v1.15.3

Removing a node

To remove a node from the cluster, use microk8s remove-node:

microk8s remove-node 10.22.254.79

Finally, on the removed node, run microk8s leave. MicroK8s will restart
its own control plane and resume operations as a full single node cluster:

microk8s leave

Last updated a month ago.