add secure cluster example scenario

docs/examples/scenarios/installing_backend_cluster/.gitignore

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+.vagrant
+.keys

docs/examples/scenarios/installing_backend_cluster/Vagrantfile

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+$lscript = <<-SCRIPT
+echo "provisioning...."
+touch /home/vagrant/.ssh/authorized_keys
+cat /vagrant/demo.pub >> /home/vagrant/.ssh/authorized_keys
+apt-get update
+apt-get install -y nginx
+cp /vagrant/conf/load-balancing.conf /etc/nginx/conf.d/
+systemctl restart nginx
+SCRIPT
+
+
+Vagrant.configure("2") do |config|
+  # Common config
+
+  # VM-specific config
+  3.times do |i|
+    config.vm.define("sensu-cluster#{i}") do |backend|
+      backend.vm.box = "centos/7" 
+      backend.vm.provision(
+        "shell",
+        inline: "cat /vagrant/demo.pub >> /home/vagrant/.ssh/authorized_keys"
+      )
+      backend.vm.hostname = "sensu-cluster#{i}"
+      backend.vm.network "private_network", ip: "192.168.50.2#{i}"
+      backend.vm.provider("virtualbox") do |v|
+        v.memory = 1024
+        v.cpus = 1
+      end
+    end
+  end
+
+
+  config.vm.define("loadbalance") do |loadbalance|
+    loadbalance.vm.provision(
+      "shell",
+      inline: $lscript 
+    )
+    loadbalance.vm.box = "hashicorp/bionic64" 
+    loadbalance.vm.hostname = "loadbalancer"
+    loadbalance.vm.network "private_network", ip: "192.168.50.30"
+    loadbalance.vm.network "forwarded_port", guest: 3000, host: 3000
+    loadbalance.vm.network "forwarded_port", guest: 8080, host: 8080
+
+    loadbalance.vm.provider("virtualbox") do |v|
+      v.memory = 1024
+      v.cpus = 1
+    end
+  end
+
+end

docs/examples/scenarios/installing_backend_cluster/cleanup_playbook.yaml

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+---
+- hosts: backends,agents
+  become: true
+  roles:
+    - geerlingguy.ntp
+
+- name: Stop Sensu-backend and purge configuration
+  hosts: backends
+  become: true
+
+  tasks:
+    - debug: var=inventory_hostname
+    - debug: var=ansible_hostname
+    - name: Stop backend
+      systemd:
+        name: sensu-backend
+        state: stopped
+      ignore_errors: true
+    - name : Remove sensu embedded etcd store
+      file:
+        path: /var/lib/sensu/sensu-backend/etcd
+        state: absent
+

docs/examples/scenarios/installing_backend_cluster/conf/load-balancing.conf

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+# WebSocket Proxy with Load Balancing
+#
+# Like the other examples, but there are three WS backends (ws1, ws2, ws3).
+# Each client must always be forwarded to the same backend (e.g. when using 
+# HTTPS requests).
+
+upstream sensu_api {
+    # Clients with the same IP are redirected to the same backend
+    ip_hash;
+
+    # Available backend servers
+    server 192.168.50.20:8080;
+    server 192.168.50.21:8080;
+    server 192.168.50.22:8080;
+}
+
+upstream sensu_dashboard {
+    # Clients with the same IP are redirected to the same backend
+    ip_hash;
+
+    # Available backend servers
+    server 192.168.50.20:3000;
+    server 192.168.50.21:3000;
+    server 192.168.50.22:3000;
+}
+
+upstream sensu_agent_ws {
+    # Clients with the same IP are redirected to the same backend
+    ip_hash;
+
+    # Available backend servers
+    server 192.168.50.20:8081;
+    server 192.168.50.21:8081;
+    server 192.168.50.22:8081;
+}
+
+
+server {
+    listen 8081;
+
+    location / {
+        ## switch off logging
+        access_log off;
+
+        # redirect all HTTP traffic to localhost:8080
+        proxy_pass http://sensu_agent_ws;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header Host $host;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+
+        # WebSocket support (nginx 1.4)
+        proxy_http_version 1.1;
+        proxy_set_header Upgrade $http_upgrade;
+        proxy_set_header Connection "upgrade";
+
+    }
+}
+server {
+    listen 8080;
+
+    location / {
+        ## switch off logging
+        access_log off;
+
+        # redirect all HTTP traffic to localhost:8080
+        proxy_pass http://sensu_api;
+        #proxy_set_header X-Real-IP $remote_addr;
+        #proxy_set_header Host $host;
+        #proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+
+        ## WebSocket support (nginx 1.4)
+        #proxy_http_version 1.1;
+        #proxy_set_header Upgrade $http_upgrade;
+        #proxy_set_header Connection "upgrade";
+
+    }
+}
+server {
+    listen 3000;
+
+    location / {
+        ## switch off logging
+        access_log off;
+
+        # redirect all HTTP traffic to localhost:8080
+        proxy_pass http://sensu_dashboard;
+
+    }
+}

docs/examples/scenarios/installing_backend_cluster/demo

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+-----END OPENSSH PRIVATE KEY-----

docs/examples/scenarios/installing_backend_cluster/demo.pub

@@ -0,0 +1 @@
+ssh-rsa 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 [email protected]

docs/examples/scenarios/installing_backend_cluster/group_vars/all/vars.yaml

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+---
+ansible_ssh_common_args: >
+  -o IdentitiesOnly=yes
+  -o BatchMode=yes
+  -o UserKnownHostsFile=/dev/null
+  -o StrictHostKeyChecking=no
+  -i demo

docs/examples/scenarios/installing_backend_cluster/inventory.yaml

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+---
+all:
+  hosts: 
+    localhost:
+      ansible_connection: local
+  children:
+    backends:
+      hosts:
+        sensu-cluster0:
+          ansible_host: 192.168.50.20
+          ansible_user: vagrant
+        sensu-cluster1:
+          ansible_host: 192.168.50.21
+          ansible_user: vagrant
+        sensu-cluster2:
+          ansible_host: 192.168.50.22
+          ansible_user: vagrant
+    agents:
+      hosts:
+        sensu-cluster0:
+          ansible_host: 192.168.50.20
+          ansible_user: vagrant