Editing K3s - Kubernetes Simplified (section)

=== Install the master nodes ===
Install the first master node with these commands.  This will put it on the node that the command is issued from ... if that is not the desire, remove the '--local' parameter
 mkdir $HOME/.kube
 export EXTRA_ARGS="--disable servicelb --disable traefik --disable local-storage --write-kubeconfig-mode=644 --flannel-backend host-gw" \
 k3sup install --cluster --local --ip <server-ip-1> --k3s-channel stable --k3s-extra-args '$EXTRA_ARGS' \
               --local-path $HOME/.kube/config --tls-san <rr-dns-name>

Explanations:
* --cluster sets this up for a HA control plane
* --local says to do it on this system, instead of using SSH to the node -- '''but you still need to provide the IP address''', otherwise it will put 127.0.0.1 as the API server address
* get the last stable version available from k3s (use 'latest' to get bleeding edge updates)
* we want to disable the simplified k3s loadbalancer ... it really is a crowbar solution and doesn't provide IP request capability
* disable the default ingress controller, as we really want something better
* disable the local storage driver (it's a pain if you're installing another storage driver)
* make the k3s.yaml file readable by the pods ... really should be by default
* (temporary workaround) force the flannel backend to use 'host-gw' mode since 'vxlan' mode seems to be broken with Debian 11
* the --local-path tells k3sup where to put the kubeconfig files ... this is the standard place, so we will put it there.  The directory has to exist -- hence the 'mkdir' command ...
* by providing the name of the DNS round robin, it should be able to pass muster on TLS connections ...

Subsequent master nodes can be installed next:
 k3sup join --server --host <new master server> --k3s-channel stable --server-host <original master server> --user ewilliam --k3s-extra-args "$EXTRA_ARGS"

Explanations:
* join as another server, not an agent/worker
* provide the hostname of the new master node to be joined
* specify the hostname of the first master created
* use the same EXTRA_ARGS provided to the first server

Repeat this for all the masters (minimum 3) providing the same server IP address of the first master.  Note that if you need to add/remove more parameters to the k3s service, you need to do it on all server nodes -- just edit the k3s.service file and restart one server at a time.

Now that you have all the masters online, reset the kubeconfig file (~/.kube/config) to use the common  name through the reverse proxy or DNS Round Robin instead of the IP of the first master:
 sed -i -e s/<server-ip-1>/<common-name>/g $HOME/.kube/config