Step-by-Step Loki Binary Deployment on Linux (CentOS/Ubuntu)

Prerequisites

Target OS: CentOS 7.x / 8.x (Ubuntu similar). Required components: Loki v3.6.10 (latest stable, GLIBC‑compatible), Promtail for log collection, Grafana for visualization.

Note: On CentOS 7 the default GLIBC is lower than 2.32; deploying v3.6.10 may fail with GLIBC_2.32/2.34 not found. Upgrade GLIBC or use an older Loki version.

1. Environment Preparation

Disable the firewall or open ports 3100, 9090, 3000.

2. Deploy Loki Server (binary)

2.1 Create directories

mkdir -p /app/soft/{bin,conf,data}
cd /app/soft/bin

2.2 Download and install Loki

wget https://github.com/grafana/loki/releases/download/v3.6.10/loki-linux-amd64.zip
unzip loki-linux-amd64.zip
chmod +x loki-linux-amd64
mv loki-linux-amd64 loki

2.3 Create Loki configuration

Save the following as /app/soft/conf/loki-config.yaml (paths adapted to /app/soft).

server:
  http_listen_port: 3100  # Loki service port
  grpc_listen_port: 9096  # gRPC port
  log_level: info

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

schema_config:
  configs:
    - from: 2025-04-08
      store: tsdb
      object_store: filesystem
      schema: v13
      index:
        prefix: index_
        period: 24h

compactor:
  working_directory: /app/soft/data/compactor
  compaction_interval: 10m
  retention_enabled: true
  retention_delete_delay: 2h
  retention_delete_worker_count: 150
  delete_request_store: filesystem

limits_config:
  retention_period: 72h

ruler:
  alertmanager_url: http://localhost:9093

frontend:
  encoding: protobuf

2.4 Create systemd service for Loki

vim /etc/systemd/system/loki.service

Service file content:

[Unit]
Description=Loki Log Aggregation System
After=network.target

[Service]
User=root
Group=root
ExecStart=/app/soft/bin/loki -config.file=/app/soft/conf/loki-config.yaml
Restart=always
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target

Reload systemd, start and enable the service, then verify:

systemctl daemon-reload
systemctl start loki
systemctl enable loki
systemctl status loki
curl localhost:3100/ready   # should return "ready"

3. Deploy Promtail (log collector)

3.1 Download and install Promtail

cd /app/soft/bin
wget https://github.com/grafana/loki/releases/download/v3.6.10/promtail-linux-amd64.zip
unzip promtail-linux-amd64.zip
chmod +x promtail-linux-amd64
mv promtail-linux-amd64 promtail

3.2 Create Promtail configuration

Save as /app/soft/conf/promtail-config.yaml:

server:
  http_listen_port: 9080
  grpc_listen_port: 0

positions:
  filename: /app/soft/data/positions.yaml

clients:
  - url: http://127.0.0.1:3100/loki/api/v1/push

scrape_configs:
  # System logs
  - job_name: system
    static_configs:
      - targets: [localhost]
        labels:
          job: system_log
          env: test
          node: localhost
    file_sd_configs:
      - files: [/app/soft/conf/system-logs.yaml]

  # Loki own logs
  - job_name: loki
    static_configs:
      - targets: [localhost]
        labels:
          job: loki_log
          env: test
          node: localhost
    file_sd_configs:
      - files: [/app/soft/conf/loki-logs.yaml]

3.3 Define log path files

System log paths ( /app/soft/conf/system-logs.yaml):

- targets:
    - localhost
  labels:
    __path__: /var/log/*.log
    __path__: /var/log/messages
    __path__: /var/log/secure

Loki log path ( /app/soft/conf/loki-logs.yaml):

- targets:
    - localhost
  labels:
    __path__: /var/log/loki.log

3.4 Create systemd service for Promtail

vim /etc/systemd/system/promtail.service

Service file content:

[Unit]
Description=Promtail Log Collector
After=network.target loki.service

[Service]
User=root
Group=root
ExecStart=/app/soft/bin/promtail -config.file=/app/soft/conf/promtail-config.yaml
Restart=always
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target

Reload systemd, start and enable Promtail, then verify its status.

systemctl daemon-reload
systemctl start promtail
systemctl enable promtail
systemctl status promtail

4. Deploy Grafana and Add Loki Datasource

Install Grafana (method omitted) and configure it to use Loki as a data source. The article includes screenshots of the Grafana UI for adding the datasource.