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.

Dhcp servers

isc-dhcp Installation Guide