Promtail

Start an HTTP endpoint to listen and receive Promtail log data and report it to Guance Cloud.

Configuration¶

Already tested version:

Collector Configuration¶

Go to the conf.d/log directory under the DataKit installation directory, copy promtail.conf.sample and name it promtail.conf. Examples are as follows:

```toml

[inputs.promtail]
  ##  When processing requests with the legacy version interface,
  ##  setting it to true corresponds to the Loki API endpoint /api/prom/push.
  #
  legacy = false

  [inputs.promtail.tags]
    # some_tag = "some_value"
    # more_tag = "some_other_value"

```
After configuration, [Restart DataKit](../datakit/datakit-service-how-to.md#manage-service).

API Version¶

For Promtail versions v0.3.0 and before, Datakit's configuration should set legacy = true, by using legacy API POST /api/prom/push to receiving logging data from Promtail.

Using the default Datakit's configuration, namely legacy = false for the rest of Promtail versions, by using new API POST /loki/api/v1/push.

Custom Tags¶

You can add custom tags to log data by configuring [inputs.promtail.tags], as shown below:

  [inputs.promtail.tags]
    some_tag = "some_value"
    more_tag = "some_other_value"

After configuration, restart DataKit.

Supported parameter¶

The Promtail collector supports adding parameters to the HTTP URL. The list of parameters is as follows:

source: Identifies the data source. Such as nginx or redis（/v1/write/promtail?source=nginx), With source set to defaultby default;
pipeline: Specify the pipeline name required for the data, Such as nginx.p（/v1/write/promtail?pipeline=nginx.p）；
tags: Add custom tags, separated by English commas ,, such as key1=value1 and key2=value2（/v1/write/promtail?tags=key1=value1,key2=value2）。

Best Practice¶

Promtail's data was originally sent to Loki, which is, /loki/api/v1/push. Change the url in Promtail's configuration to Datakit, after enabled Datakit's Promtail collector, Promtail would send its data to Datakit's Promtail collector.

Promtail's configuration is like below:

server:
  http_listen_port: 9080
  grpc_listen_port: 0

positions:
  filename: /tmp/positions.yaml

clients:
  - url: http://localhost:9529/v1/write/promtail    # Send to the endpoint that the promtail collector listens on

scrape_configs:
  - job_name: system
    static_configs:
      - targets:
          - localhost
        labels:
          job: varlogs
          __path__: /var/log/*log

Logging¶

The logs delivered by Promtail shall prevail.