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Capstone Project 4 — Configure a DHCP Server

In this capstone project, you'll build a production-ready DHCP (Dynamic Host Configuration Protocol) server that automatically assigns IP addresses and network configuration to client devices. You'll configure DHCP scopes, reservations, lease times, multiple subnets, DHCP relay, and integrate DHCP with DNS. DHCP is one of the most important infrastructure services because it automates network configuration and simplifies device management. Every Network Engineer, DevOps Engineer, Platform Engineer, Cloud Engineer, and System Administrator should understand how to deploy and manage DHCP services.

Learning Path

Networking Mastery → Module 15: Capstone Projects → Project 4

Difficulty: Advanced

Estimated Completion Time: 5–8 Hours

Course Progress

Course: Networking Mastery

Module: Capstone Projects

Project: 4 of 8

Project Objectives

By completing this project, you'll be able to:

  • Deploy a Linux DHCP server
  • Configure DHCP scopes
  • Create IP reservations
  • Configure lease times
  • Support multiple VLANs and subnets
  • Integrate DHCP with DNS
  • Troubleshoot DHCP issues

Skills Covered

This project combines concepts from:

  • DHCP
  • IP Addressing
  • DNS
  • VLANs
  • Routing
  • Linux Networking
  • Firewalls
  • Network Troubleshooting

Project Scenario

Currently, every workstation is configured manually.

Problems include:

  • IP conflicts
  • Incorrect gateway settings
  • DNS configuration errors
  • High administrative effort

Your task is to automate IP address assignment using DHCP.

Target Architecture

                Internet
                    │
                 Router
                    │
               Core Switch
                    │
      ┌─────────────┴─────────────┐
      │                           │
 DHCP Server                 Client Devices
      │
 DNS Server

Clients automatically receive network configuration.

Lab Requirements

Software:

  • Ubuntu Server LTS
  • Debian
  • Rocky Linux

Recommended:

  • Ubuntu Server LTS

Network Design

Device IP Address
DHCP Server 192.168.20.10
DNS Server 192.168.20.20
Gateway 192.168.20.1
Clients Dynamic

Step 1 — Install DHCP Server

Ubuntu:

sudo apt update

sudo apt install isc-dhcp-server -y

Verify installation.

Step 2 — Configure Network Interface

Identify interface:

ip addr

Configure DHCP service to listen on:

eth0

(or your active interface)

Step 3 — Configure DHCP Scope

Example subnet:

192.168.20.0/24

DHCP Pool:

192.168.20.100

↓

192.168.20.200

Reserved addresses remain available for servers and infrastructure.

Step 4 — Configure Gateway

Default gateway:

192.168.20.1

Clients automatically receive the correct gateway.

Step 5 — Configure DNS

Provide:

192.168.20.20

Clients automatically use the internal DNS server.

Step 6 — Configure Domain Name

Example:

company.local

Clients receive:

server.company.local

for internal name resolution.

Step 7 — Configure Lease Time

Example:

Default Lease:

8 Hours

Maximum Lease:

24 Hours

Lease durations should balance network efficiency and address availability.

Step 8 — Restart DHCP Service

sudo systemctl restart isc-dhcp-server

Verify:

sudo systemctl status isc-dhcp-server

Step 9 — Configure Client

Release current lease:

sudo dhclient -r

Request a new lease:

sudo dhclient

Verify:

ip addr

Step 10 — Verify Assigned Configuration

Check:

  • IP Address
  • Gateway
  • DNS Server
  • Lease Duration

Verify connectivity.

Step 11 — Configure DHCP Reservation

Reserve an address for a server.

Example:

MAC Address

↓

192.168.20.50

Critical systems should receive consistent IP addresses.

Step 12 — Configure Multiple Subnets

Example:

VLAN Network
Users 192.168.10.0/24
Servers 192.168.20.0/24
DevOps 192.168.30.0/24
Guest 192.168.40.0/24

Create a DHCP scope for each subnet.

Step 13 — Configure DHCP Relay

When DHCP server and clients are on different VLANs:

Client

↓

Relay Agent

↓

DHCP Server

The relay forwards DHCP requests across routed networks.

Step 14 — Configure Firewall

Allow DHCP traffic.

Ports:

Protocol Port
UDP 67
UDP 68

Verify clients can communicate with the server.

Step 15 — Verify Logs

View logs:

journalctl -u isc-dhcp-server

Confirm:

  • Lease Requests
  • Lease Assignments
  • Errors
  • Service Startup

Enterprise DHCP Architecture

Clients
     │
     │
Core Switch
     │
DHCP Relay
     │
DHCP Server
     │
DNS Server

Large organizations commonly centralize DHCP services.

DHCP and DNS Integration

Workflow:

Client

↓

DHCP

↓

IP Assigned

↓

DNS Registration

↓

Name Resolution

This enables automatic hostname registration.

Security Improvements

Implement:

  • DHCP Reservations for Critical Systems
  • DHCP Snooping
  • Restrict Unauthorized DHCP Servers
  • Firewall Protection
  • Logging
  • Backup DHCP Configuration

Validation Checklist

Item Status
DHCP Installed ☐
Scope Configured ☐
Gateway Configured ☐
DNS Configured ☐
Lease Times Configured ☐
Client Receives Address ☐
Reservation Tested ☐
Firewall Updated ☐
Logs Verified ☐
Documentation Updated ☐

Common Problems

Problem Solution
No IP Assigned Verify DHCP Service
Incorrect Gateway Check Scope Configuration
DNS Missing Verify DHCP Options
Duplicate IP Review Reservations
Cross-VLAN Failure Verify DHCP Relay

Troubleshooting Commands

Check interface.

ip addr

Restart DHCP.

sudo systemctl restart isc-dhcp-server

View logs.

journalctl -u isc-dhcp-server

Renew lease.

sudo dhclient

Release lease.

sudo dhclient -r

Bonus Challenges

Extend the project by:

  • Configuring High Availability DHCP
  • Deploying DHCP Failover
  • Integrating with Active Directory
  • Automating DHCP Configuration
  • Deploying Multiple DHCP Servers
  • Monitoring DHCP Leases with Prometheus
  • Implementing DHCP Snooping on Switches

Learning Outcomes

After completing this project, you'll be able to:

  • Deploy enterprise DHCP infrastructure
  • Configure multiple DHCP scopes
  • Create IP reservations
  • Integrate DHCP with DNS
  • Configure DHCP relay
  • Troubleshoot DHCP services

Project Deliverables

By the end of this project, you should have:

  • Working DHCP Server
  • DHCP Scope
  • Gateway Configuration
  • DNS Configuration
  • Lease Policies
  • Static Reservations
  • DHCP Relay (Optional)
  • Firewall Rules
  • Documentation

Self-Assessment

Before moving to the next project, confirm:

  • Can you install and configure a DHCP server?
  • Can you create DHCP scopes?
  • Can you configure lease durations?
  • Can you configure DHCP reservations?
  • Can you support multiple VLANs?
  • Can you troubleshoot DHCP issues?
  • Can you document the DHCP infrastructure?

Summary

In this capstone project, you deployed a production-ready DHCP server and automated IP address assignment for client systems. You configured DHCP scopes, reservations, lease policies, DNS integration, multiple subnets, and DHCP relay while validating client connectivity and service availability.

This project reflects real-world enterprise environments where DHCP automates network configuration, reduces administrative overhead, and ensures consistent, scalable IP address management.

Key Takeaways

  • DHCP automates IP address assignment and client network configuration.
  • Configure separate DHCP scopes for each subnet or VLAN.
  • Use reservations for servers, printers, and network infrastructure.
  • Deploy DHCP relay when clients and servers are separated by routers.
  • Integrate DHCP with DNS for seamless hostname resolution.
  • Protect DHCP infrastructure with logging, firewall rules, and DHCP snooping where supported.

What's Next?

Build a VPN Server

In the next capstone project, you'll learn how to Build a VPN Server.

You'll deploy a secure remote access VPN using Linux, configure encrypted tunnels, manage user authentication, implement firewall rules, enable secure access to internal resources, and troubleshoot VPN connectivity in a production-style environment.