Add support for deploying Prometheus libvirt exporter

Add support for deploying the Kolla Prometheus libvirt exporter
image to facilitate gathering metrics from the Nova libvirt service.

Partially-Implements: blueprint libvirt-exporter
(cherry picked from commit edcd41a)
(cherry picked from commit ab84608)

Change-Id: Ife0a9ac6e4f03802543d0812d552c30ddb982b9e
(cherry picked from commit 1422e0e)

Author: dougszumski

ansible/group_vars/all.yml

@@ -431,6 +431,7 @@ placement_api_port: "8780"
 placement_api_listen_port: "{{ placement_api_port }}"
 
 prometheus_port: "9091"
+prometheus_libvirt_exporter_port: "9177"
 prometheus_node_exporter_port: "9100"
 prometheus_mysqld_exporter_port: "9104"
 prometheus_haproxy_exporter_port: "9101"
@@ -1093,6 +1094,7 @@ use_common_mariadb_user: "no"
 # Prometheus
 ############
 enable_prometheus_server: "{{ enable_prometheus | bool }}"
+enable_prometheus_libvirt_exporter: "no"
 enable_prometheus_haproxy_exporter: "{{ enable_haproxy | bool }}"
 enable_prometheus_mysqld_exporter: "{{ enable_mariadb | bool }}"
 enable_prometheus_node_exporter: "{{ enable_prometheus | bool }}"
@@ -1105,6 +1107,7 @@ enable_prometheus_elasticsearch_exporter: "{{ enable_prometheus | bool and enabl
 enable_prometheus_blackbox_exporter: "{{ enable_prometheus | bool }}"
 
 prometheus_alertmanager_user: "admin"
+prometheus_libvirt_exporter_interval: "60s"
 prometheus_openstack_exporter_interval: "60s"
 prometheus_elasticsearch_exporter_interval: "60s"
 prometheus_cmdline_extras:

ansible/inventory/all-in-one

@@ -732,6 +732,9 @@ compute
 network
 storage
 
+[prometheus-libvirt-exporter:children]
+compute
+
 [prometheus-mysqld-exporter:children]
 mariadb
 

ansible/inventory/multinode

@@ -750,6 +750,9 @@ compute
 network
 storage
 
+[prometheus-libvirt-exporter:children]
+compute
+
 [prometheus-mysqld-exporter:children]
 mariadb
 

ansible/roles/nova-cell/defaults/main.yml

@@ -330,6 +330,7 @@ nova_libvirt_default_volumes:
   - "/sys/fs/cgroup:/sys/fs/cgroup"
   - "kolla_logs:/var/log/kolla/"
   - "libvirtd:/var/lib/libvirt"
+  - "{% if enable_prometheus_libvirt_exporter | bool %}libvirtd_run:/var/run/libvirt{% endif %}"
   - "{{ nova_instance_datadir_volume }}:/var/lib/nova/"
   - "{% if enable_shared_var_lib_nova_mnt | bool %}/var/lib/nova/mnt:/var/lib/nova/mnt:shared{% endif %}"
   - "nova_libvirt_qemu:/etc/libvirt/qemu"

ansible/roles/prometheus/defaults/main.yml

@@ -23,6 +23,13 @@ prometheus_services:
     pid_mode: "host"
     volumes: "{{ prometheus_node_exporter_default_volumes + prometheus_node_exporter_extra_volumes }}"
     dimensions: "{{ prometheus_node_exporter_dimensions }}"
+  prometheus-libvirt-exporter:
+    container_name: "prometheus_libvirt_exporter"
+    group: "prometheus-libvirt-exporter"
+    enabled: "{{ enable_prometheus_libvirt_exporter | bool }}"
+    image: "{{ prometheus_libvirt_exporter_image_full }}"
+    volumes: "{{ prometheus_libvirt_exporter_default_volumes + prometheus_libvirt_exporter_extra_volumes }}"
+    dimensions: "{{ prometheus_libvirt_exporter_dimensions }}"
   prometheus-mysqld-exporter:
     container_name: prometheus_mysqld_exporter
     group: prometheus-mysqld-exporter
@@ -123,6 +130,10 @@ prometheus_server_image: "{{ docker_registry ~ '/' if docker_registry else '' }}
 prometheus_server_tag: "{{ prometheus_tag }}"
 prometheus_server_image_full: "{{ prometheus_server_image }}:{{ prometheus_server_tag }}"
 
+prometheus_libvirt_exporter_image: "{{ docker_registry ~ '/' if docker_registry else '' }}{{ docker_namespace }}/{{ kolla_base_distro }}-{{ prometheus_install_type }}-prometheus-libvirt-exporter"
+prometheus_libvirt_exporter_tag: "{{ prometheus_tag }}"
+prometheus_libvirt_exporter_image_full: "{{ prometheus_libvirt_exporter_image }}:{{ prometheus_libvirt_exporter_tag }}"
+
 prometheus_haproxy_exporter_image: "{{ docker_registry ~ '/' if docker_registry else '' }}{{ docker_namespace }}/{{ kolla_base_distro }}-{{ prometheus_install_type }}-prometheus-haproxy-exporter"
 prometheus_haproxy_exporter_tag: "{{ prometheus_tag }}"
 prometheus_haproxy_exporter_image_full: "{{ prometheus_haproxy_exporter_image }}:{{ prometheus_haproxy_exporter_tag }}"
@@ -161,6 +172,7 @@ prometheus_blackbox_exporter_tag: "{{ prometheus_tag }}"
 prometheus_blackbox_exporter_image_full: "{{ prometheus_blackbox_exporter_image }}:{{ prometheus_blackbox_exporter_tag }}"
 
 prometheus_server_dimensions: "{{ default_container_dimensions }}"
+prometheus_libvirt_exporter_dimensions: "{{ default_container_dimensions }}"
 prometheus_haproxy_exporter_dimensions: "{{ default_container_dimensions }}"
 prometheus_mysqld_exporter_dimensions: "{{ default_container_dimensions }}"
 prometheus_node_exporter_dimensions: "{{ default_container_dimensions }}"
@@ -177,6 +189,10 @@ prometheus_server_default_volumes:
   - "{{ '/etc/timezone:/etc/timezone:ro' if ansible_os_family == 'Debian' else '' }}"
   - "prometheus:/var/lib/prometheus"
   - "kolla_logs:/var/log/kolla/"
+prometheus_libvirt_exporter_default_volumes:
+  - "{{ node_config_directory }}/prometheus-libvirt-exporter/:{{ container_config_directory }}/:ro"
+  - "/etc/localtime:/etc/localtime:ro"
+  - "libvirtd_run:/var/run/libvirt:ro"
 prometheus_haproxy_exporter_default_volumes:
   - "{{ node_config_directory }}/prometheus-haproxy-exporter/:{{ container_config_directory }}/:ro"
   - "/etc/localtime:/etc/localtime:ro"
@@ -233,6 +249,7 @@ prometheus_blackbox_exporter_default_volumes:
   - "kolla_logs:/var/log/kolla/"
 
 prometheus_extra_volumes: "{{ default_extra_volumes }}"
+prometheus_libvirt_exporter_extra_volumes: "{{ prometheus_extra_volumes }}"
 prometheus_server_extra_volumes: "{{ prometheus_extra_volumes }}"
 prometheus_haproxy_exporter_extra_volumes: "{{ prometheus_extra_volumes }}"
 prometheus_mysqld_exporter_extra_volumes: "{{ prometheus_extra_volumes }}"

ansible/roles/prometheus/handlers/main.yml

@@ -149,3 +149,18 @@
     dimensions: "{{ service.dimensions }}"
   when:
     - kolla_action != "config"
+
+- name: Restart prometheus-libvirt-exporter container
+  vars:
+    service_name: "prometheus-libvirt-exporter"
+    service: "{{ prometheus_services[service_name] }}"
+  become: true
+  kolla_docker:
+    action: "recreate_or_restart_container"
+    common_options: "{{ docker_common_options }}"
+    name: "{{ service.container_name }}"
+    image: "{{ service.image }}"
+    volumes: "{{ service.volumes }}"
+    dimensions: "{{ service.dimensions }}"
+  when:
+    - kolla_action != "config"

ansible/roles/prometheus/tasks/precheck.yml

@@ -19,6 +19,7 @@
       - prometheus_openstack_exporter
       - prometheus_elasticsearch_exporter
       - prometheus_blackbox_exporter
+      - prometheus_libvirt_exporter
   register: container_facts
 
 - name: Checking free port for Prometheus server
@@ -149,3 +150,17 @@
     - enable_prometheus_blackbox_exporter | bool
   with_items:
     - "{{ prometheus_blackbox_exporter_port }}"
+
+- name: Checking free ports for Prometheus libvirt-exporter
+  wait_for:
+    host: "{{ hostvars[inventory_hostname]['ansible_' + api_interface]['ipv4']['address'] }}"
+    port: "{{ item }}"
+    connect_timeout: 1
+    timeout: 1
+    state: stopped
+  when:
+    - container_facts['prometheus_libvirt_exporter'] is not defined
+    - inventory_hostname in groups['prometheus-libvirt-exporter']
+    - enable_prometheus_libvirt_exporter | bool
+  with_items:
+    - "{{ prometheus_libvirt_exporter_port }}"

ansible/roles/prometheus/templates/prometheus-libvirt-exporter.json.j2

@@ -0,0 +1,4 @@
+{
+    "command": "/opt/libvirt_exporter --web.listen-address={{ api_interface_address }}:{{ prometheus_libvirt_exporter_port }}",
+    "config_files": []
+}

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

@@ -126,6 +126,17 @@ scrape_configs:
         replacement: '{{ api_interface_address | put_address_in_context('url') }}:{{ prometheus_blackbox_exporter_port }}'
 {% endif %}
 
+
+{% if enable_prometheus_libvirt_exporter | bool %}
+  - job_name: libvirt_exporter
+    scrape_interval: {{ prometheus_libvirt_exporter_interval }}
+    static_configs:
+      - targets:
+{% for host in groups["prometheus-libvirt-exporter"] %}
+        - '{{ hostvars[host]['ansible_' + hostvars[host]['api_interface']]['ipv4']['address'] }}:{{ hostvars[host]['prometheus_libvirt_exporter_port'] }}'
+{% endfor %}
+{% endif %}
+
 {% if enable_prometheus_alertmanager | bool %}
 alerting:
   alertmanagers:

etc/kolla/globals.yml

@@ -654,6 +654,7 @@
 # Prometheus
 ############
 #enable_prometheus_server: "{{ enable_prometheus | bool }}"
+#enable_prometheus_libvirt_exporter: "no"
 #enable_prometheus_haproxy_exporter: "{{ enable_haproxy | bool }}"
 #enable_prometheus_mysqld_exporter: "{{ enable_mariadb | bool }}"
 #enable_prometheus_node_exporter: "{{ enable_prometheus | bool }}"