Grafana – Install Loki

A Loki-based logging stack consists of 3 components:

• Promtail is the agent, responsible for gathering logs and sending them to Loki.
• Loki is the main server, responsible for storing logs and processing queries.
• Grafana for querying and displaying the logs.

• Download Loki

wget https://github.com/grafana/loki/releases/download/v2.9.8/loki-linux-amd64.zip
chmod a+x loki-linux-amd64
sudo cp loki-linux-amd64 /usr/local/bin/loki
loki --version

• Create Systemd service

sudo nano /etc/systemd/system/loki.service

[Unit]
Description=Loki is a log aggregation system designed to store and query logs from all your applications and infrastructure.
Document=https://github.com/grafana/loki/releases
After=network.target

[Service]
Type=simple
ExecStart=/usr/local/bin/loki -config.file /mnt/data/loki/loki-config.yaml
Restart=on-failure
RestartSec=10
StandardOutput=append:/mnt/data/loki/logs/loki.log
StandardError=append:/mnt/data/loki/logs/loki.log

[Install]
WantedBy=multi-user.target

# This is a complete configuration to deploy Loki backed by the filesystem.
# The index will be shipped to the storage via tsdb-shipper.

auth_enabled: false

server:
  http_listen_port: 3100

common:
  ring:
    instance_addr: 127.0.0.1
    kvstore:
      store: inmemory
  replication_factor: 1
  path_prefix: /mnt/data/loki
  storage:
    filesystem:
      chunks_directory: /mnt/data/loki/chunks
      rules_directory: /mnt/data/loki/rules

schema_config:
  configs:
  - from: 2020-05-15
    store: tsdb
    object_store: filesystem
    schema: v13
    index:
      prefix: index_
      period: 24h

storage_config:
  filesystem:
    directory: /mnt/data/loki/chunks

Promtail

PROMTAIL_VERSION=$(curl -s "https://api.github.com/repos/grafana/loki/releases/latest" | grep -Po '"tag_name": "v\K[0-9.]+')

sudo mkdir /opt/promtail

sudo wget -qO /opt/promtail/promtail.gz "https://github.com/grafana/loki/releases/download/v${PROMTAIL_VERSION}/promtail-linux-amd64.zip"

sudo gunzip /opt/promtail/promtail.gz

sudo chmod a+x /opt/promtail/promtail

sudo ln -s /opt/promtail/promtail /usr/local/bin/promtail

sudo wget -qO /opt/promtail/promtail-local-config.yaml "https://raw.githubusercontent.com/grafana/loki/v${PROMTAIL_VERSION}/clients/cmd/promtail/promtail-local-config.yaml"

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

[Unit]
Description=Promtail client for sending logs to Loki
Documentation=https://grafana.com/docs/loki/latest/send-data/promtail/
After=network.target

[Service]
Type=simple
User=root
ExecStart=/opt/promtail/promtail -config.file=/opt/promtail/promtail-local-config.yaml
Restart=always
TimeoutStopSec=3

[Install]
WantedBy=multi-user.target