MetalLB as loadbalancer for on premise deployments (#3027)

* add metallb as loadbalancer for on premise deployments

* improve configuration

* add variables to DaemonSet

contrib/metallb/README.md

+# Deploy MetalLB into Kubespray/Kubernetes
+```
+MetalLB hooks into your Kubernetes cluster, and provides a network load-balancer implementation. In short, it allows you to create Kubernetes services of type “LoadBalancer” in clusters that don’t run on a cloud provider, and thus cannot simply hook into paid products to provide load-balancers.
+```
+This playbook aims to automate [this](https://metallb.universe.tf/tutorial/layer2/tutorial). It deploys MetalLB into kubernetes and sets up a layer 2 loadbalancer.
+
+## Install
+```
+ansible-playbook --ask-become -i inventory/sample/k8s_heketi_inventory.yml contrib/metallb/metallb.yml
+```

contrib/metallb/metallb.yml

+---
+- hosts: kube-master[0]
+  tags:
+    - "provision"
+  roles:
+    - { role: provision }

contrib/metallb/roles/provision/defaults/main.yml

+---
+metallb:
+  ip_range: "10.5.0.50-10.5.0.99"
+  limits:
+    cpu: "100m"
+    memory: "100Mi"
+  port: "7472"

contrib/metallb/roles/provision/tasks/main.yml

+---
+- name: "Kubernetes Apps | Lay Down MetalLB"
+  become: true
+  template: { src: "{{ item }}.j2", dest: "{{ kube_config_dir }}/{{ item }}" }
+  with_items: ["metallb.yml", "metallb-config.yml"]
+  register: "rendering"
+  when:
+    - "inventory_hostname == groups['kube-master'][0]"
+- name: "Kubernetes Apps | Install and configure MetalLB"
+  kube:
+    name: "MetalLB"
+    filename: "{{ kube_config_dir }}/metallb.yml"
+    state: "{{ item.changed | ternary('latest','present') }}"
+  with_items: "{{ rendering.results }}"
+  when:
+    - "inventory_hostname == groups['kube-master'][0]"

contrib/metallb/roles/provision/templates/metallb-config.yml.j2

+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  namespace: metallb-system
+  name: config
+data:
+  config: |
+    address-pools:
+    - name: loadbalanced
+      protocol: layer2
+      addresses:
+      - {{ metallb.ip_range }}

contrib/metallb/roles/provision/templates/metallb.yml.j2

+apiVersion: v1
+kind: Namespace
+metadata:
+  name: metallb-system
+  labels:
+    app: metallb
+---
+
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  namespace: metallb-system
+  name: controller
+  labels:
+    app: metallb
+---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  namespace: metallb-system
+  name: speaker
+  labels:
+    app: metallb
+
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: metallb-system:controller
+  labels:
+    app: metallb
+rules:
+- apiGroups: [""]
+  resources: ["services"]
+  verbs: ["get", "list", "watch", "update"]
+- apiGroups: [""]
+  resources: ["services/status"]
+  verbs: ["update"]
+- apiGroups: [""]
+  resources: ["events"]
+  verbs: ["create", "patch"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: metallb-system:speaker
+  labels:
+    app: metallb
+rules:
+- apiGroups: [""]
+  resources: ["services", "endpoints", "nodes"]
+  verbs: ["get", "list", "watch"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: Role
+metadata:
+  namespace: metallb-system
+  name: leader-election
+  labels:
+    app: metallb
+rules:
+- apiGroups: [""]
+  resources: ["endpoints"]
+  resourceNames: ["metallb-speaker"]
+  verbs: ["get", "update"]
+- apiGroups: [""]
+  resources: ["endpoints"]
+  verbs: ["create"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: Role
+metadata:
+  namespace: metallb-system
+  name: config-watcher
+  labels:
+    app: metallb
+rules:
+- apiGroups: [""]
+  resources: ["configmaps"]
+  verbs: ["get", "list", "watch"]
+- apiGroups: [""]
+  resources: ["events"]
+  verbs: ["create"]
+---
+
+## Role bindings
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: metallb-system:controller
+  labels:
+    app: metallb
+subjects:
+- kind: ServiceAccount
+  name: controller
+  namespace: metallb-system
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: metallb-system:controller
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: metallb-system:speaker
+  labels:
+    app: metallb
+subjects:
+- kind: ServiceAccount
+  name: speaker
+  namespace: metallb-system
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: metallb-system:speaker
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: RoleBinding
+metadata:
+  namespace: metallb-system
+  name: config-watcher
+  labels:
+    app: metallb
+subjects:
+- kind: ServiceAccount
+  name: controller
+- kind: ServiceAccount
+  name: speaker
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: Role
+  name: config-watcher
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: RoleBinding
+metadata:
+  namespace: metallb-system
+  name: leader-election
+  labels:
+    app: metallb
+subjects:
+- kind: ServiceAccount
+  name: speaker
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: Role
+  name: leader-election
+---
+apiVersion: apps/v1beta2
+kind: DaemonSet
+metadata:
+  namespace: metallb-system
+  name: speaker
+  labels:
+    app: metallb
+    component: speaker
+spec:
+  selector:
+    matchLabels:
+      app: metallb
+      component: speaker
+  template:
+    metadata:
+      labels:
+        app: metallb
+        component: speaker
+      annotations:
+        prometheus.io/scrape: "true"
+        prometheus.io/port: "{{ metallb.port }}"
+    spec:
+      serviceAccountName: speaker
+      terminationGracePeriodSeconds: 0
+      hostNetwork: true
+      containers:
+      - name: speaker
+        image: metallb/speaker:v0.6.2
+        imagePullPolicy: IfNotPresent
+        args:
+        - --port={{ metallb.port }}
+        - --config=config
+        env:
+        - name: METALLB_NODE_NAME
+          valueFrom:
+            fieldRef:
+              fieldPath: spec.nodeName
+        ports:
+        - name: monitoring
+          containerPort: {{ metallb.port }}
+        resources:
+          limits:
+            cpu: {{ metallb.limits.cpu }}
+            memory: {{ metallb.limits.memory }}
+        securityContext:
+          allowPrivilegeEscalation: false
+          readOnlyRootFilesystem: true
+          capabilities:
+            drop:
+            - all
+            add:
+            - net_raw
+
+---
+apiVersion: apps/v1beta2
+kind: Deployment
+metadata:
+  namespace: metallb-system
+  name: controller
+  labels:
+    app: metallb
+    component: controller
+spec:
+  revisionHistoryLimit: 3
+  selector:
+    matchLabels:
+      app: metallb
+      component: controller
+  template:
+    metadata:
+      labels:
+        app: metallb
+        component: controller
+      annotations:
+        prometheus.io/scrape: "true"
+        prometheus.io/port: "{{ metallb.port }}"
+    spec:
+      serviceAccountName: controller
+      terminationGracePeriodSeconds: 0
+      securityContext:
+        runAsNonRoot: true
+        runAsUser: 65534 # nobody
+      containers:
+      - name: controller
+        image: metallb/controller:v0.6.2
+        imagePullPolicy: IfNotPresent
+        args:
+        - --port={{ metallb.port }}
+        - --config=config
+        ports:
+        - name: monitoring
+          containerPort: {{ metallb.port }}
+        resources:
+          limits:
+            cpu: {{ metallb.limits.cpu }}
+            memory: {{ metallb.limits.memory }}
+        securityContext:
+          allowPrivilegeEscalation: false
+          capabilities:
+            drop:
+            - all
+          readOnlyRootFilesystem: true
+
+---
+
+