Adds etcd endpoints as a Prometheus scrape target

Add "enable_prometheus_etcd_integration" configuration parameter which
can be used to configure Prometheus to scrape etcd metrics endpoints.
The default value of "enable_prometheus_etcd_integration" is set to
the combined values of "enable_prometheus" and "enable_etcd".

Change-Id: I7a0b802c5687e2d508e06baf55e355d9761e806f

ansible/group_vars/all.yml

@@ -457,6 +457,7 @@ prometheus_rabbitmq_exporter_port: "{{ rabbitmq_prometheus_port }}"
 prometheus_cadvisor_port: "18080"
 prometheus_fluentd_integration_port: "24231"
 prometheus_libvirt_exporter_port: "9177"
+prometheus_etcd_integration_port: "{{ etcd_client_port }}"
 
 # Prometheus alertmanager ports
 prometheus_alertmanager_port: "9093"
@@ -1109,6 +1110,7 @@ enable_prometheus_elasticsearch_exporter: "{{ enable_prometheus | bool and enabl
 enable_prometheus_blackbox_exporter: "{{ enable_prometheus | bool }}"
 enable_prometheus_rabbitmq_exporter: "{{ enable_prometheus | bool and enable_rabbitmq | bool }}"
 enable_prometheus_libvirt_exporter: "{{ enable_prometheus | bool and enable_nova | bool and nova_compute_virt_type in ['kvm', 'qemu'] }}"
+enable_prometheus_etcd_integration: "{{ enable_prometheus | bool and enable_etcd | bool }}"
 
 prometheus_alertmanager_user: "admin"
 prometheus_openstack_exporter_interval: "60s"

ansible/roles/prometheus/templates/prometheus.yml.j2

@@ -156,6 +156,15 @@ scrape_configs:
 {% endfor %}
 {% endif %}
 
+{% if enable_prometheus_etcd_integration | bool %}
+  - job_name: etcd
+    static_configs:
+      - targets:
+{% for host in groups["etcd"] %}
+        - '{{ 'api' | kolla_address(host) | put_address_in_context('url') }}:{{ hostvars[host]['prometheus_etcd_integration_port'] }}'
+{% endfor %}
+{% endif %}
+
 {% if enable_prometheus_alertmanager | bool %}
   - job_name: alertmanager
     static_configs:

etc/kolla/globals.yml

@@ -710,6 +710,7 @@
 #enable_prometheus_elasticsearch_exporter: "{{ enable_prometheus | bool and enable_elasticsearch | bool }}"
 #enable_prometheus_blackbox_exporter: "{{ enable_prometheus | bool }}"
 #enable_prometheus_libvirt_exporter: "{{ enable_prometheus | bool and enable_nova | bool and nova_compute_virt_type in ['kvm', 'qemu'] }}"
+#enable_prometheus_etcd_integration: "{{ enable_prometheus | bool and enable_etcd | bool }}"
 
 # List of extra parameters passed to prometheus. You can add as many to the list.
 #prometheus_cmdline_extras:

releasenotes/notes/support-etcd-metrics-fdfb8f3da96dd761.yaml

@@ -0,0 +1,7 @@
+---
+features:
+  - |
+    Add ``enable_prometheus_etcd_integration`` configuration parameter which
+    can be used to configure Prometheus to scrape etcd metrics endpoints.
+    The default value of ``enable_prometheus_etcd_integration`` is set to
+    the combined values of ``enable_prometheus`` and ``enable_etcd``.