MetalLB install script for bare metal cluster

If Ingress controller is exposed via NodePort
it listens on non standard port, so it can be
quite problematic.  Exposing via LoadBalancer
doesn't work properly on bare metal Kubernetes
cluster, so external LB solution is needed.

Signed-off-by: Lucjan Bryndza <l.bryndza@samsung.com>
Change-Id: I9a2032e8501caca7c3a564f6bbcf969fdde31da2
Issue-ID: OOM-2346

diff --git a/kubernetes/contrib/metallb-loadbalancer-inst/install-metallb-on-cluster.sh b/kubernetes/contrib/metallb-loadbalancer-inst/install-metallb-on-cluster.sh
new file mode 100755 (executable)
index 0000000..6e412a3
--- /dev/null
+++ b/kubernetes/contrib/metallb-loadbalancer-inst/install-metallb-on-cluster.sh
@@ -0,0 +1,85 @@
+#!/bin/bash -e
+#
+#   Copyright 2020 Samsung Electronics Co., Ltd.
+#
+#   Licensed under the Apache License, Version 2.0 (the "License");
+#   you may not use this file except in compliance with the License.
+#   You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+#   Unless required by applicable law or agreed to in writing, software
+#   distributed under the License is distributed on an "AS IS" BASIS,
+#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#   See the License for the specific language governing permissions and
+#   limitations under the License.
+#
+
+usage() {
+cat << ==usage
+$0 Automatic configuration using external addresess from nodes
+$0 --help This message
+$0 -h This message
+$0 [cluster_ip1] ... [cluster_ipn]  Cluster address or ip ranges
+==usage
+}
+
+
+find_nodes_with_external_addrs()
+{
+       local WORKER_NODES=$(kubectl get no -l node-role.kubernetes.io/worker=true -o jsonpath='{.items..metadata.name}')
+       for worker in $WORKER_NODES; do
+               local external_ip=$(kubectl get no $worker  -o jsonpath='{.metadata.annotations.rke\.cattle\.io/external-ip }')
+               local internal_ip=$(kubectl get no $worker  -o jsonpath='{.metadata.annotations.rke\.cattle\.io/internal-ip }')
+               if [ $internal_ip != $external_ip ]; then
+                       echo $external_ip
+               fi
+       done
+}
+
+generate_config_map()
+{
+cat <<CNFEOF | kubectl apply -f -
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  namespace: metallb-system
+  name: config
+data:
+  config: |
+    address-pools:
+    - name: default
+      protocol: layer2
+      addresses:
+$(for value in "$@"; do echo -e "      - $value"; done)
+CNFEOF
+}
+
+generate_config_from_single_addr() {
+       generate_config_map "$1 - $1"
+}
+
+install_metallb() {
+       kubectl apply -f https://raw.githubusercontent.com/google/metallb/v0.9.3/manifests/namespace.yaml
+       kubectl apply -f https://raw.githubusercontent.com/google/metallb/v0.9.3/manifests/metallb.yaml
+       # Only when install
+       kubectl create secret generic -n metallb-system memberlist --from-literal=secretkey="$(openssl rand -base64 128)"
+}
+
+automatic_configuration() {
+       install_metallb
+       generate_config_from_single_addr $(find_nodes_with_external_addrs)
+}
+
+manual_configuration() {
+       install_metallb
+       generate_config_map $@
+}
+
+if [[ $# -eq 1 ]] && [[ $1 == "-h" || $1 == "--help" ]]; then
+       usage
+elif [[ $# -eq 0 ]]; then
+       automatic_configuration
+else
+       manual_configuration $@
+fi