Skip to content
Snippets Groups Projects
prometheus-guide.rst 5.68 KiB
Newer Older
  • Learn to ignore specific revisions
  • .. _prometheus-guide:
    
    =====================================================
    Prometheus - Monitoring System & Time Series Database
    =====================================================
    
    Overview
    ~~~~~~~~
    
    Kolla can deploy a full working Prometheus setup in either a **all-in-one** or
    **multinode** setup.
    
    Preparation and deployment
    ~~~~~~~~~~~~~~~~~~~~~~~~~~
    
    To enable Prometheus, modify the configuration file ``/etc/kolla/globals.yml``
    and change the following:
    
    .. code-block:: yaml
    
       enable_prometheus: "yes"
    
    
    This will, by default, deploy Prometheus version 2.x. Since Prometheus 1.x data
    is not compatible with Prometheus 2.x and no automatic data migration is
    provided, any previous Prometheus 1.x deployment will be replaced and all its
    stored metrics will become inacessible (but still available in the old data
    volume: ``prometheus``; the new data volume defaults to ``prometheus_v2``).
    If you rely on Prometheus only as e.g. a source of alert notifications (in pair
    with Alertmanager), it might not be worth migrating old metrics and they could
    be discarded. Otherwise, it's either possible to use
    `remote storage <https://prometheus.io/docs/prometheus/latest/storage/#remote-storage-integrations>`_
    or scrape Kolla's Prometheus ``/federate`` endpoint with an external system.
    However, if you want to stay on 1.x series, set the following variable:
    
    .. code-block:: yaml
    
       prometheus_use_v1: yes
    
    
    .. warning::
       Support for Prometheus 1.x is deprecated and will be removed in next
       Kolla Ansible release (Xena).
    
    
    In order to remove leftover volume containing Prometheus 1.x data, execute:
    
    .. code-block:: console
    
       docker volume rm prometheus
    
    on all hosts wherever Prometheus was previously deployed.
    
    
    Extending the default command line options
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    
    It is possible to extend the default command line options for Prometheus by
    
    using a custom variable. As an example, to set query timeout to 1 minute
    and data retention size to 30 gigabytes:
    
       prometheus_cmdline_extras: "--query.timeout=1m --storage.tsdb.retention.size=30GB"
    
    
    Extending prometheus.cfg
    ~~~~~~~~~~~~~~~~~~~~~~~~
    
    If you want to add extra targets to scrape, you can extend the default
    ``prometheus.yml`` config file by placing additional configs in
    ``{{ node_custom_config }}/prometheus/prometheus.yml.d``. These should have the
    same format as ``prometheus.yml``. These additional configs are merged so
    that any list items are extended. For example, if using the default value for
    ``node_custom_config``, you could add additional targets to scape by defining
    ``/etc/kolla/config/prometheus/prometheus.yml.d/10-custom.yml`` containing the
    following:
    
    .. code-block:: jinja
    
      scrape_configs:
        - job_name: custom
          static_configs:
            - targets:
              - '10.0.0.111:1234'
        - job_name: custom-template
          static_configs:
            - targets:
      {% for host in groups['prometheus'] %}
              - '{{ hostvars[host]['ansible_' + hostvars[host]['api_interface']]['ipv4']['address'] }}:{{ 3456 }}'
      {% endfor %}
    
    The jobs, ``custom``, and ``custom_template``  would be appended to the default
    list of ``scrape_configs`` in the final ``prometheus.yml``. To customize on a per
    host basis, files can also be placed in
    ``{{ node_custom_config }}/prometheus/<inventory_hostname>/prometheus.yml.d``
    where, ``inventory_hostname`` is one of the hosts in your inventory. These
    will be merged with any files in ``{{ node_custom_config }}/prometheus/prometheus.yml.d``,
    so in order to override a list value instead of extending it, you will need to make
    sure that no files in ``{{ node_custom_config }}/prometheus/prometheus.yml.d``
    set a key with an equivalent hierarchical path.
    
    
    Extra files
    ~~~~~~~~~~~
    
    Sometimes it is necessary to reference additional files from within
    ``prometheus.yml``, for example, when defining file service discovery
    configuration. To enable you to do this, kolla-ansible will resursively
    discover any files in ``{{ node_custom_config }}/prometheus/extras`` and
    template them. The templated output is then copied to
    ``/etc/prometheus/extras`` within the container on startup. For example to
    configure `ipmi_exporter <https://github.com/soundcloud/ipmi_exporter>`_, using
    the default value for ``node_custom_config``, you could create the following
    files:
    
    - ``/etc/kolla/config/prometheus/prometheus.yml.d/ipmi-exporter.yml``:
    
        .. code-block:: jinja
    
            ---
            scrape_configs:
            - job_name: ipmi
              params:
                module: ["default"]
                scrape_interval: 1m
                scrape_timeout: 30s
                metrics_path: /ipmi
                scheme: http
                file_sd_configs:
                  - files:
                      - /etc/prometheus/extras/file_sd/ipmi-exporter-targets.yml
                refresh_interval: 5m
                relabel_configs:
                  - source_labels: [__address__]
                    separator: ;
                    regex: (.*)
                    target_label: __param_target
                    replacement: ${1}
                    action: replace
                  - source_labels: [__param_target]
                    separator: ;
                    regex: (.*)
                    target_label: instance
                    replacement: ${1}
                    action: replace
                  - separator: ;
                    regex: .*
                    target_label: __address__
                    replacement: "{{ ipmi_exporter_listen_address }}:9290"
                    action: replace
    
      where ``ipmi_exporter_listen_address`` is a variable containing the IP address of
      the node where the exporter is running.
    
    -  ``/etc/kolla/config/prometheus/extras/file_sd/ipmi-exporter-targets.yml``:
        .. code-block:: yaml
    
            ---
            - targets:
              - 192.168.1.1
            labels:
                job: ipmi_exporter