nagios Installation Guide Installation Guide

nagios is a free and open-source system monitoring. Nagios provides comprehensive IT infrastructure monitoring

Hardware Requirements:

CPU: 2+ cores

RAM: 2GB minimum

Storage: 5GB for data

Network: HTTP/check protocols

Operating System:

Linux: Any modern distribution (RHEL, Debian, Ubuntu, CentOS, Fedora, Arch, Alpine, openSUSE)

macOS: 10.14+ (Mojave or newer)

Windows: Windows Server 2016+ or Windows 10

FreeBSD: 11.0+

Network Requirements:

Port 80 (default nagios port)

NRPE on 5666

Dependencies:

See official documentation for specific requirements

System Access: root or sudo privileges required

This guide supports installation on:

RHEL 8/9 and derivatives (CentOS Stream, Rocky Linux, AlmaLinux)

Debian 11/12

Ubuntu 20.04/22.04/24.04 LTS

Arch Linux (rolling release)

Alpine Linux 3.18+

openSUSE Leap 15.5+ / Tumbleweed

SUSE Linux Enterprise Server (SLES) 15+

macOS 12+ (Monterey and later)

FreeBSD 13+

Windows 10/11/Server 2019+ (where applicable)

bash

# Install EPEL repository if needed
sudo dnf install -y epel-release

# Install nagios
sudo dnf install -y nagios

# Enable and start service
sudo systemctl enable --now nagios

# Configure firewall
sudo firewall-cmd --permanent --add-port=80/tcp
sudo firewall-cmd --reload

# Verify installation
nagios --version

bash

# Update package index
sudo apt update

# Install nagios
sudo apt install -y nagios

# Enable and start service
sudo systemctl enable --now nagios

# Configure firewall
sudo ufw allow 80

# Verify installation
nagios --version

bash

# Install nagios
sudo pacman -S nagios

# Enable and start service
sudo systemctl enable --now nagios

# Verify installation
nagios --version

bash

# Install nagios
apk add --no-cache nagios

# Enable and start service
rc-update add nagios default
rc-service nagios start

# Verify installation
nagios --version

bash

# Install nagios
sudo zypper install -y nagios

# Enable and start service
sudo systemctl enable --now nagios

# Configure firewall
sudo firewall-cmd --permanent --add-port=80/tcp
sudo firewall-cmd --reload

# Verify installation
nagios --version

bash

# Using Homebrew
brew install nagios

# Start service
brew services start nagios

# Verify installation
nagios --version

bash

# Using pkg
pkg install nagios

# Enable in rc.conf
echo 'nagios_enable="YES"' >> /etc/rc.conf

# Start service
service nagios start

# Verify installation
nagios --version

bash

# Using Chocolatey
choco install nagios

# Or using Scoop
scoop install nagios

# Verify installation
nagios --version

bash

# Create configuration directory
sudo mkdir -p /etc/nagios

# Set up basic configuration
# See official documentation for detailed configuration options

# Test configuration
nagios --version

bash

# Enable service
sudo systemctl enable nagios

# Start service
sudo systemctl start nagios

# Stop service
sudo systemctl stop nagios

# Restart service
sudo systemctl restart nagios

# Check status
sudo systemctl status nagios

# View logs
sudo journalctl -u nagios -f

bash

# Enable service
rc-update add nagios default

# Start service
rc-service nagios start

# Stop service
rc-service nagios stop

# Restart service
rc-service nagios restart

# Check status
rc-service nagios status

bash

# Enable in /etc/rc.conf
echo 'nagios_enable="YES"' >> /etc/rc.conf

# Start service
service nagios start

# Stop service
service nagios stop

# Restart service
service nagios restart

# Check status
service nagios status

bash

# Using Homebrew services
brew services start nagios
brew services stop nagios
brew services restart nagios

# Check status
brew services list | grep nagios

powershell

# Start service
net start nagios

# Stop service
net stop nagios

# Using PowerShell
Start-Service nagios
Stop-Service nagios
Restart-Service nagios

# Check status
Get-Service nagios

See the official documentation for advanced configuration options.

nginx

upstream nagios_backend {
    server 127.0.0.1:80;
}

server {
    listen 80;
    server_name nagios.example.com;
    return 301 https://$server_name$request_uri;
}

server {
    listen 443 ssl http2;
    server_name nagios.example.com;

    ssl_certificate /etc/ssl/certs/nagios.example.com.crt;
    ssl_certificate_key /etc/ssl/private/nagios.example.com.key;

    location / {
        proxy_pass http://nagios_backend;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}

apache

<VirtualHost *:80>
    ServerName nagios.example.com
    Redirect permanent / https://nagios.example.com/
</VirtualHost>

<VirtualHost *:443>
    ServerName nagios.example.com
    
    SSLEngine on
    SSLCertificateFile /etc/ssl/certs/nagios.example.com.crt
    SSLCertificateKeyFile /etc/ssl/private/nagios.example.com.key
    
    ProxyRequests Off
    ProxyPreserveHost On
    
    ProxyPass / http://127.0.0.1:80/
    ProxyPassReverse / http://127.0.0.1:80/
</VirtualHost>

haproxy

frontend nagios_frontend
    bind *:80
    bind *:443 ssl crt /etc/ssl/certs/nagios.pem
    redirect scheme https if !{ ssl_fc }
    default_backend nagios_backend

backend nagios_backend
    balance roundrobin
    server nagios1 127.0.0.1:80 check

bash

# Set appropriate permissions
sudo chown -R nagios:nagios /etc/nagios
sudo chmod 750 /etc/nagios

# Configure firewall
sudo firewall-cmd --permanent --add-port=80/tcp
sudo firewall-cmd --reload

# Enable SELinux policies (if applicable)
sudo setsebool -P httpd_can_network_connect on

See official documentation for database configuration requirements.

bash

# Basic system tuning
echo 'net.core.somaxconn = 65535' | sudo tee -a /etc/sysctl.conf
echo 'net.ipv4.tcp_max_syn_backlog = 65535' | sudo tee -a /etc/sysctl.conf
sudo sysctl -p

bash

# Check service status
sudo systemctl status nagios

# View logs
sudo journalctl -u nagios -f

# Monitor resource usage
top -p $(pgrep nagios)

bash

#!/bin/bash
# Basic backup script
BACKUP_DIR="/backup/nagios"
DATE=$(date +%Y%m%d_%H%M%S)

mkdir -p "$BACKUP_DIR"
tar -czf "$BACKUP_DIR/nagios-backup-$DATE.tar.gz" /etc/nagios /var/lib/nagios

echo "Backup completed: $BACKUP_DIR/nagios-backup-$DATE.tar.gz"

bash

# Stop service
sudo systemctl stop nagios

# Restore from backup
tar -xzf /backup/nagios/nagios-backup-*.tar.gz -C /

# Start service
sudo systemctl start nagios

1. Service won't start:

bash

# Check logs
sudo journalctl -u nagios -n 100
sudo tail -f /var/log/nagios/nagios.log

# Check configuration
nagios --version

# Check permissions
ls -la /etc/nagios

2. Connection issues:

bash

# Check if service is listening
sudo ss -tlnp | grep 80

# Test connectivity
telnet localhost 80

# Check firewall
sudo firewall-cmd --list-all

3. Performance issues:

bash

# Check resource usage
top -p $(pgrep nagios)

# Check disk I/O
iotop -p $(pgrep nagios)

# Check connections
ss -an | grep 80

yaml

version: '3.8'
services:
  nagios:
    image: nagios:latest
    ports:
      - "80:80"
    volumes:
      - ./config:/etc/nagios
      - ./data:/var/lib/nagios
    restart: unless-stopped

Maintenance

bash

# RHEL/CentOS/Rocky/AlmaLinux
sudo dnf update nagios

# Debian/Ubuntu
sudo apt update && sudo apt upgrade nagios

# Arch Linux
sudo pacman -Syu nagios

# Alpine Linux
apk update && apk upgrade nagios

# openSUSE
sudo zypper update nagios

# FreeBSD
pkg update && pkg upgrade nagios

# Always backup before updates
tar -czf /backup/nagios-pre-update-$(date +%Y%m%d).tar.gz /etc/nagios

# Restart after updates
sudo systemctl restart nagios

Regular Maintenance

bash

# Log rotation
sudo logrotate -f /etc/logrotate.d/nagios

# Clean old logs
find /var/log/nagios -name "*.log" -mtime +30 -delete

# Check disk usage
du -sh /var/lib/nagios

Official Documentation: https://docs.nagios.org/

GitHub Repository: https://github.com/nagios/nagios

Community Forum: https://forum.nagios.org/

Best Practices Guide: https://docs.nagios.org/best-practices

---

Note: This guide is part of the HowToMgr collection. Always refer to official documentation for the most up-to-date information.

1. Prerequisites

2. Supported Operating Systems

3. Installation

RHEL/CentOS/Rocky Linux/AlmaLinux

Debian/Ubuntu

Arch Linux

Alpine Linux

openSUSE/SLES

macOS

FreeBSD

Windows

Initial Configuration

Basic Configuration

5. Service Management

systemd (RHEL, Debian, Ubuntu, Arch, openSUSE)

OpenRC (Alpine Linux)

rc.d (FreeBSD)

launchd (macOS)

Windows Service Manager

Advanced Configuration

Reverse Proxy Setup

nginx Configuration

Apache Configuration

HAProxy Configuration

Security Configuration

Basic Security Setup

Database Setup

Performance Optimization

System Tuning

Monitoring

Basic Monitoring

9. Backup and Restore

Backup Script

Restore Procedure

6. Troubleshooting

Common Issues

Integration Examples

Docker Compose Example

Maintenance

Update Procedures

Regular Maintenance

Additional Resources

Related Monitoring Guides

Blackbox Exporter Installation Guide

blackbox-exporter Installation Guide

mysqld-exporter Installation Guide