isc-dhcp Installation Guide Installation Guide

isc-dhcp is a free and open-source DHCP server and client. ISC DHCP provides robust DHCP services for automatic network configuration, the reference implementation of DHCP

Hardware Requirements:

CPU: 1 core minimum

RAM: 128MB minimum

Storage: 50MB for installation

Network: UDP ports 67-68

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 67 (default isc-dhcp port)

Port 68 for client

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 isc-dhcp
sudo dnf install -y isc-dhcp-server

# Enable and start service
sudo systemctl enable --now isc-dhcp-server

# Configure firewall
sudo firewall-cmd --permanent --add-port=67/tcp
sudo firewall-cmd --reload

# Verify installation
dhcpd --version

bash

# Update package index
sudo apt update

# Install isc-dhcp
sudo apt install -y isc-dhcp-server

# Enable and start service
sudo systemctl enable --now isc-dhcp-server

# Configure firewall
sudo ufw allow 67

# Verify installation
dhcpd --version

bash

# Install isc-dhcp
sudo pacman -S isc-dhcp-server

# Enable and start service
sudo systemctl enable --now isc-dhcp-server

# Verify installation
dhcpd --version

bash

# Install isc-dhcp
apk add --no-cache isc-dhcp-server

# Enable and start service
rc-update add isc-dhcp-server default
rc-service isc-dhcp-server start

# Verify installation
dhcpd --version

bash

# Install isc-dhcp
sudo zypper install -y isc-dhcp-server

# Enable and start service
sudo systemctl enable --now isc-dhcp-server

# Configure firewall
sudo firewall-cmd --permanent --add-port=67/tcp
sudo firewall-cmd --reload

# Verify installation
dhcpd --version

bash

# Using Homebrew
brew install isc-dhcp-server

# Start service
brew services start isc-dhcp-server

# Verify installation
dhcpd --version

bash

# Using pkg
pkg install isc-dhcp-server

# Enable in rc.conf
echo 'isc-dhcp-server_enable="YES"' >> /etc/rc.conf

# Start service
service isc-dhcp-server start

# Verify installation
dhcpd --version

bash

# Using Chocolatey
choco install isc-dhcp-server

# Or using Scoop
scoop install isc-dhcp-server

# Verify installation
dhcpd --version

bash

# Create configuration directory
sudo mkdir -p /etc/isc-dhcp-server

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

# Test configuration
dhcpd --version

bash

# Enable service
sudo systemctl enable isc-dhcp-server

# Start service
sudo systemctl start isc-dhcp-server

# Stop service
sudo systemctl stop isc-dhcp-server

# Restart service
sudo systemctl restart isc-dhcp-server

# Check status
sudo systemctl status isc-dhcp-server

# View logs
sudo journalctl -u isc-dhcp-server -f

bash

# Enable service
rc-update add isc-dhcp-server default

# Start service
rc-service isc-dhcp-server start

# Stop service
rc-service isc-dhcp-server stop

# Restart service
rc-service isc-dhcp-server restart

# Check status
rc-service isc-dhcp-server status

bash

# Enable in /etc/rc.conf
echo 'isc-dhcp-server_enable="YES"' >> /etc/rc.conf

# Start service
service isc-dhcp-server start

# Stop service
service isc-dhcp-server stop

# Restart service
service isc-dhcp-server restart

# Check status
service isc-dhcp-server status

bash

# Using Homebrew services
brew services start isc-dhcp-server
brew services stop isc-dhcp-server
brew services restart isc-dhcp-server

# Check status
brew services list | grep isc-dhcp-server

powershell

# Start service
net start isc-dhcp-server

# Stop service
net stop isc-dhcp-server

# Using PowerShell
Start-Service isc-dhcp-server
Stop-Service isc-dhcp-server
Restart-Service isc-dhcp-server

# Check status
Get-Service isc-dhcp-server

See the official documentation for advanced configuration options.

nginx

upstream isc-dhcp-server_backend {
    server 127.0.0.1:67;
}

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

server {
    listen 443 ssl http2;
    server_name isc-dhcp-server.example.com;

    ssl_certificate /etc/ssl/certs/isc-dhcp-server.example.com.crt;
    ssl_certificate_key /etc/ssl/private/isc-dhcp-server.example.com.key;

    location / {
        proxy_pass http://isc-dhcp-server_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 isc-dhcp-server.example.com
    Redirect permanent / https://isc-dhcp-server.example.com/
</VirtualHost>

<VirtualHost *:443>
    ServerName isc-dhcp-server.example.com
    
    SSLEngine on
    SSLCertificateFile /etc/ssl/certs/isc-dhcp-server.example.com.crt
    SSLCertificateKeyFile /etc/ssl/private/isc-dhcp-server.example.com.key
    
    ProxyRequests Off
    ProxyPreserveHost On
    
    ProxyPass / http://127.0.0.1:67/
    ProxyPassReverse / http://127.0.0.1:67/
</VirtualHost>

haproxy

frontend isc-dhcp-server_frontend
    bind *:80
    bind *:443 ssl crt /etc/ssl/certs/isc-dhcp-server.pem
    redirect scheme https if !{ ssl_fc }
    default_backend isc-dhcp-server_backend

backend isc-dhcp-server_backend
    balance roundrobin
    server isc-dhcp-server1 127.0.0.1:67 check

bash

# Set appropriate permissions
sudo chown -R isc-dhcp-server:isc-dhcp-server /etc/isc-dhcp-server
sudo chmod 750 /etc/isc-dhcp-server

# Configure firewall
sudo firewall-cmd --permanent --add-port=67/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 isc-dhcp-server

# View logs
sudo journalctl -u isc-dhcp-server -f

# Monitor resource usage
top -p $(pgrep isc-dhcp-server)

bash

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

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

echo "Backup completed: $BACKUP_DIR/isc-dhcp-server-backup-$DATE.tar.gz"

bash

# Stop service
sudo systemctl stop isc-dhcp-server

# Restore from backup
tar -xzf /backup/isc-dhcp-server/isc-dhcp-server-backup-*.tar.gz -C /

# Start service
sudo systemctl start isc-dhcp-server

1. Service won't start:

bash

# Check logs
sudo journalctl -u isc-dhcp-server -n 100
sudo tail -f /var/log/isc-dhcp-server/isc-dhcp-server.log

# Check configuration
dhcpd --version

# Check permissions
ls -la /etc/isc-dhcp-server

2. Connection issues:

bash

# Check if service is listening
sudo ss -tlnp | grep 67

# Test connectivity
telnet localhost 67

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

3. Performance issues:

bash

# Check resource usage
top -p $(pgrep isc-dhcp-server)

# Check disk I/O
iotop -p $(pgrep isc-dhcp-server)

# Check connections
ss -an | grep 67

yaml

version: '3.8'
services:
  isc-dhcp-server:
    image: isc-dhcp-server:latest
    ports:
      - "67:67"
    volumes:
      - ./config:/etc/isc-dhcp-server
      - ./data:/var/lib/isc-dhcp-server
    restart: unless-stopped

Maintenance

bash

# RHEL/CentOS/Rocky/AlmaLinux
sudo dnf update isc-dhcp-server

# Debian/Ubuntu
sudo apt update && sudo apt upgrade isc-dhcp-server

# Arch Linux
sudo pacman -Syu isc-dhcp-server

# Alpine Linux
apk update && apk upgrade isc-dhcp-server

# openSUSE
sudo zypper update isc-dhcp-server

# FreeBSD
pkg update && pkg upgrade isc-dhcp-server

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

# Restart after updates
sudo systemctl restart isc-dhcp-server

Regular Maintenance

bash

# Log rotation
sudo logrotate -f /etc/logrotate.d/isc-dhcp-server

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

# Check disk usage
du -sh /var/lib/isc-dhcp-server

Official Documentation: https://docs.isc-dhcp-server.org/

GitHub Repository: https://github.com/isc-dhcp-server/isc-dhcp-server

Community Forum: https://forum.isc-dhcp-server.org/

Best Practices Guide: https://docs.isc-dhcp-server.org/best-practices

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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