Warning

This version of ScalarDB is no longer supported. For details, see the Release Support Policy.

Getting Started with Helm Charts (Logging using Loki Stack)

This document explains how to get started with log aggregation for Scalar products on Kubernetes using Grafana Loki (with Promtail).

We assume that you have already read the getting-started with monitoring for Scalar products and installed kube-prometheus-stack.

What we create

We will deploy the following components on a Kubernetes cluster as follows.

+--------------------------------------------------------------------------------------------------+
| +------------------------------------+                                                           |
| |             loki-stack             |                                                           |
| |                                    |                                       +-----------------+ |
| | +--------------+  +--------------+ | <-----------------(Log)-------------- | Scalar Products | |
| | |     Loki     |  |   Promtail   | |                                       |                 | |
| | +--------------+  +--------------+ |                                       |  +-----------+  | |
| +------------------------------------+                                       |  | ScalarDB  |  | |
|                                                                              |  +-----------+  | |
| +------------------------------------------------------+                     |                 | |
| |                kube-prometheus-stack                 |                     |  +-----------+  | |
| |                                                      |                     |  | ScalarDL  |  | |
| | +--------------+  +--------------+  +--------------+ | -----(Monitor)----> |  +-----------+  | |
| | |  Prometheus  |  | Alertmanager |  |   Grafana    | |                     +-----------------+ |
| | +-------+------+  +------+-------+  +------+-------+ |                                         |
| |         |                |                 |         |                                         |
| |         +----------------+-----------------+         |                                         |
| |                          |                           |                                         |
| +--------------------------+---------------------------+                                         |
|                            |                                                                     |
|                            |         Kubernetes                                                  |
+----------------------------+---------------------------------------------------------------------+
                             | <- expose to localhost (127.0.0.1) or use load balancer etc to access
                             |
              (Access Dashboard through HTTP)
                             |
                        +----+----+
                        | Browser |
                        +---------+

Step 1. Prepare a custom values file

  1. Get the sample file scalar-loki-stack-custom-values.yaml for the loki-stack helm chart.

Step 2. Deploy loki-stack

  1. Add the grafana helm repository.

    helm repo add grafana https://grafana.github.io/helm-charts
    
  2. Deploy the loki-stack helm chart.

    helm install scalar-logging-loki grafana/loki-stack -n monitoring -f scalar-loki-stack-custom-values.yaml
    

Step 3. Add a Loki data source in the Grafana configuration

  1. Add a configuration of the Loki data source in the scalar-prometheus-custom-values.yaml file.

    grafana:
      additionalDataSources:
      - name: Loki
        type: loki
        uid: loki
        url: http://scalar-logging-loki:3100/
        access: proxy
        editable: false
        isDefault: false
    
  2. Apply the configuration (upgrade the deployment of kube-prometheus-stack).

    helm upgrade scalar-monitoring prometheus-community/kube-prometheus-stack -n monitoring -f scalar-prometheus-custom-values.yaml
    

Step 4. Access the Grafana dashboard

  1. Add Loki as a data source
    • Go to Grafana http://localhost:3000 (If you use minikube)
    • Go to Explore to find the added Loki
    • You can see the collected logs in the Explore page

Step 5. Delete the loki-stack helm chart

  1. Uninstall loki-stack.

    helm uninstall scalar-logging-loki -n monitoring