Cherry-pick-3.2-620-Adding control-plane nodes" - Requires tls-sans to be set for LB (#955)

* Edited content based on the information in the issue (#947)

Signed-off-by: Ranjini M N <ranjini.n@suse.com>

* Updated EOF

Co-authored-by: Eduardo Mínguez <e.minguez@gmail.com>

---------

Signed-off-by: Ranjini M N <ranjini.n@suse.com>
Co-authored-by: Eduardo Mínguez <e.minguez@gmail.com>

Author: ranjinimn

asciidoc/guides/metallb-kube-api.adoc

@@ -288,21 +288,29 @@ Now execute the commands below on the second and third nodes.
 For RKE2:
 [,bash]
 ----
-# Export the VIP_SERVICE_IP in the VM
-# Replace with the actual IP
-export VIP_SERVICE_IP=<ip>
-
-curl -sfL https://get.rke2.io | INSTALL_RKE2_TYPE="server" sh -
-systemctl enable rke2-server.service
-
+# As a root user, create the /etc/rancher/rke2/config.yaml config file with the following content:
 
 mkdir -p /etc/rancher/rke2/
 cat <<EOF > /etc/rancher/rke2/config.yaml
+# An example of the config.yaml file for an agent node: 
 server: https://${VIP_SERVICE_IP}:9345
+write-kubeconfig-mode: "0644"
+tls-san:
+  - "${VIP_SERVICE_IP}"
+  - "https://${VIP_SERVICE_IP}.sslip.io"
+# The one from above
 token: ${RKE2_TOKEN}
 EOF
 
-systemctl start rke2-server.service
+# Install RKE2
+curl -sfL https://get.rke2.io | INSTALL_RKE2_TYPE="server" sh -
+
+# Enable the RKE2 service with the configuration specified in the config.yaml file
+
+systemctl enable --now rke2-server.service
+
+# Fetch the cluster token to be used later:
+RKE2_TOKEN=$(tr -d '\n' < /var/lib/rancher/rke2/server/node-token)
 ----
 
 For K3s: