Promtail Installation

Promtail is an app for transferring logs from one server to another. For our use we are transferring logs from our many different VPS to our centralized Loki server.

Installing Promtail

Begin by downloading the promtail app and installing it

curl -O -L https://github.com/grafana/loki/releases/download/v2.3.0/promtail-linux-amd64.zip
sudo apt install unzip
unzip promtail-linux-amd64.zip
sudo mv promtail-linux-amd64 /usr/local/bin/promtail

make conf file

Make a configuration file for Promtail

sudo vim /etc/metrics/promtail.yml

server:
  http_listen_port: 9080
  grpc_listen_port: 0

positions:
  filename: /etc/metrics/positions.yaml

clients:
  - url: http://$METRIC_SERVER_IP:3100/loki/api/v1/push

scrape_configs:
- job_name: system
  static_configs:
  - targets:
      - localhost
    labels:
      job: system logs
      host: $HOSTNAME
      __path__: /var/log/*log

create service

We need to create the service that runs Promtail

sudo vim /etc/systemd/system/promtail.service

[Unit]
Description=Promtail service
After=network.target

[Service]
Type=simple
User=root
ExecStart=/usr/local/bin/promtail -config.file /etc/metrics/promtail.yml

[Install]
WantedBy=multi-user.target

start and enable service

Now we will start the service and enable it so that it starts automatically on restarts

sudo systemctl start promtail.service
sudo sytemctl status promtail.service
sudo systemctl enable promtail.service

open firewall on LOKI server

Finally we will need to open the firewall on the LOKI server that collects the logs

sudo ufw allow from $REMOTE_IP proto tcp to any port 3100

Instructions adapted from https://github.com/grafana/loki/releases/