Get logs into Loki
After you install and run Loki, you probably want to get logs from other applications into it.
To get application logs into Loki, you need to edit the Promtail config file.
Detailed information about configuring Promtail is available in Promtail configuration.
The following instructions should help you get started.
- If you haven’t already, download a Promtail configuration file. Keep track of where it is, because you will need to cite it when you run the binary.
- Open the config file in the text editor of your choice. It should look similar to this:
server: http_listen_port: 9080 grpc_listen_port: 0 positions: filename: /tmp/positions.yaml clients: - url: http://loki:3100/loki/api/v1/push scrape_configs: - job_name: system static_configs: - targets: - localhost labels: job: varlogs __path__: /var/log/*log
The seven lines under
scrape_configs are what send the logs that Loki generates to Loki, which then outputs them in the command line and http://localhost:3100/metrics.
Copy the seven lines under
scrape_configs, and then paste them under the original job (you can also just edit the original seven lines).
Below is an example that sends logs from a default Grafana installation to Loki. We updated the following fields:
- job_name - This differentiates the logs collected from other log groups.
- targets - Optional for static_configs, however is often defined because in older versions of Promtail it was not optional. This was an artifact from directly using the Prometheus service discovery code which required this entry.
- labels - Static label to apply to every log line scraped by this definition. Good examples would be environment name, job name, or app name.
- path - The path to where the logs are stored that I want Loki to consume.
- job_name: grafana static_configs: - targets: - grafana labels: job: grafana __path__: "C:/Program Files/GrafanaLabs/grafana/data/log/grafana.log"
- Enter the following command to run Promtail. Examples below assume you have put the config file in the same directory as the binary.
You should now see your application logs. If you are using Grafana, you might need to refresh your instance in order to see the logs.