add snmp exporter from fabbs

defaults/main.yml

@@ -42,6 +42,20 @@ prometheus_agent:
       jobs: {}
     promtail:
       enable: False
+    snmp:
+      enable: False
+      mib_path: /usr/share/snmp/mibs
+      args:
+        "web.listen-address": "[::1]:9116"
+        "config.file": "/etc/prometheus/snmp.yml"
+      # A list of objects containing a single key, either `url` or `file`, e.g.:
+      # - url: https://example.com/path/to/mib
+      # - file: /path/to/mib
+      mibs: []
+      # Generator configuration, see https://github.com/prometheus/snmp_exporter/blob/main/generator/generator.yml
+      config:
+        modules: {}
+      jobs: {}
   scrape_timeout: ~
   scrape_interval: ~
   metrics_path: ~

handlers/main.yml

@@ -17,3 +17,8 @@
   service:
     name: grafana-promtail
     state: restarted
+
+- name: restart snmp exporter
+  service:
+    name: prometheus-snmp-exporter
+    state: restarted

tasks/main.yml

@@ -38,6 +38,61 @@
       dest: /etc/prometheus/blackbox.yml
       content: "{{ prometheus_agent.agents.blackbox.config|to_nice_yaml(indent=2) }}"
 
+- name: handle snmp exporter
+  when: prometheus_agent.agents.snmp.enable
+  block:
+  - name: install prometheus-snmp-exporter
+    apt:
+      name: prometheus-snmp-exporter
+  - name: install snmp downloader
+    apt:
+      name: snmp-mibs-downloader
+    register: mibs_downloader_installed
+  - name: create folder for MIBs
+    file:
+      dest: '{{prometheus_agent.agents.snmp.mib_path }}'
+      state: directory
+  - name: download MIBs
+    loop: '{{ prometheus_agent.agents.snmp.mibs }}'
+    when: "'url' in item"
+    get_url:
+      dest: '{{prometheus_agent.agents.snmp.mib_path }}'
+      url: '{{ item.url }}'
+    #async: 600
+    #poll: 0.1
+    register: mibs_downloaded
+  - name: copy MIBs
+    loop: '{{ prometheus_agent.agents.snmp.mibs }}'
+    when: "'file' in item"
+    copy:
+      dest: '{{prometheus_agent.agents.snmp.mib_path }}'
+      src: '{{ item.file }}'
+    #async: 600
+    #poll: 0.1
+    register: mibs_copied
+  - name: create snmp directory
+    file:
+      dest: /etc/prometheus/snmp
+      state: directory
+      mode: 0755
+  - name: generate generator configuration
+    copy:
+      dest: /etc/prometheus/snmp/generator.yml
+      content: '{{ prometheus_agent.agents.snmp.config|to_nice_yaml }}'
+      mode: 0644
+    register: snmp_exporter_generator
+  - name: generate SNMP exporter configuration
+    when: snmp_exporter_generator.changed or mibs_downloader_installed.changed or mibs_downloaded.changed or mibs_copied.changed
+    shell: prometheus-snmp-generator generate -o /etc/prometheus/snmp.yml
+    args:
+      chdir: /etc/prometheus/snmp
+    notify: restart snmp exporter
+  - name: enable and start snmp exporter
+    service:
+      name: prometheus-snmp-exporter
+      state: started
+      enabled: yes
+
 - name: manage tls
   when: prometheus_agent.tls.manage
   block:

templates/node-scraper.j2

@@ -55,6 +55,41 @@
 {% endfor %}
 {% endif %}
 
+{% if prometheus_agent.scrapers[item].snmp|d(False) and prometheus_agent.agents.snmp.enable %}
+{% for j in prometheus_agent.agents.snmp.jobs %}
+{% set job=prometheus_agent.agents.snmp.jobs[j] %}
+- job_name: "prometheus-agent - snmp - {{ j }} : {{ inventory_hostname }}"
+  scheme: https
+  metrics_path: /snmp
+  static_configs:
+    - targets:
+{% for target in job.targets %}
+      - {{ target }}
+{% endfor %}
+      labels: {{ merged_prometheus_labels|combine(job.labels|d({}))|to_json }}
+{% for i in ['scrape_timeout', 'scrape_interval'] if (prometheus_agent|combine(prometheus_agent.agents.snmp)|combine(job))[i] %}
+  {{ i }}: {{ (prometheus_agent|combine(job))[i] }}
+{% endfor %}
+  tls_config:
+    ca_file: /etc/prometheus/targetcerts/{{ inventory_hostname }}.crt
+    cert_file: /etc/ssl/prometheus_scraper.crt
+    key_file: /etc/ssl/private/prometheus_scraper.key
+  params:
+    module: [{{ job.module }}]
+  relabel_configs:
+  - source_labels: [__address__]
+    target_label: __param_target
+  - source_labels: [__param_target]
+    target_label: instance
+  - replacement: 'snmp'
+    target_label: job
+  - replacement: '{{ job.module }}'
+    target_label: module
+  - target_label: __address__
+    replacement: {{ inventory_hostname }}:{{ prometheus_agent.scrapers[item].snmp }}
+{% endfor %}
+{% endif %}
+
 {% for j in prometheus_agent.scrapers[item].proxy|d({}) %}
 - job_name: "prometheus-agent - proxy - {{ j }} : {{ inventory_hostname }}"
   scheme: https

templates/stunnel-client.conf.j2

@@ -39,6 +39,19 @@ verifyPeer  = yes
 CAfile      = /etc/ssl/scraper_{{ i }}.crt
 {% endfor %}
 
+{% for i in prometheus_agent.scrapers if "snmp" in prometheus_agent.scrapers[i] and prometheus_agent.agents.snmp.enable %}
+; snmp
+[scraper {{ i }} snmp]
+client      = no
+requireCert = yes
+accept      = :::{{ prometheus_agent.scrapers[i].snmp }}
+connect     = {{ prometheus_agent.agents.snmp.args['web.listen-address']|replace('[', '')|replace(']', '') }}
+cert        = /etc/ssl/prometheus_agent.crt
+key         = /etc/ssl/private/prometheus_agent.key
+verifyPeer  = yes
+CAfile      = /etc/ssl/scraper_{{ i }}.crt
+{% endfor %}
+
 ; proxy
 {% for i in prometheus_agent.scrapers if "proxy" in prometheus_agent.scrapers[i] %}
 {% for j in prometheus_agent.scrapers[i].proxy|d({}) %}