🏢 Enterprise VLAN & Inter-VLAN Routing Setup

A Cisco Packet Tracer lab demonstrating VLAN segmentation, trunking, and router-on-a-stick inter-VLAN routing for enterprise networks.

Table of Contents

1. 📘 Project Overview
2. 🎯 Project Objectives
3. 🌐 Network Topology
4. 📝 IP Addressing Table
5. 🛠️ Lab Steps
6. 💻 Device Configuration
   • 🔀 Switch Configuration
   • 🚦 Router Configuration
   • 📡 DHCP Server Configuration
   • 🖧 PC and Server Configuration
7. ✅ Verification Commands
8. ⚡ How to Run Lab
9. 📂 Folder Structure
10. 🎓 Learning Outcomes
11. ℹ️ Repository Info

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📘 Project Overview

This lab simulates a realistic enterprise network with multiple VLANs and inter-VLAN routing implemented using router-on-a-stick.
The network includes a central switch, a router with subinterfaces, multiple PCs in different VLANs, and a server.
Key CCNA skills demonstrated include VLAN creation, trunk configuration, inter-VLAN routing, DHCP, and IP addressing.

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🎯 Project Objectives

• Configure VLANs and assign access ports.
• Configure a trunk port between switch and router.
• Configure router-on-a-stick subinterfaces for inter-VLAN routing.
• Verify connectivity between VLANs and to a central server.
• Demonstrate Layer 2 and Layer 3 network communication.

Real-world Scenario:

The company has three departments: HR, IT, and Sales. Each department needs its own VLAN for traffic segmentation. All PCs should communicate internally while maintaining proper gateway configuration, and DHCP automates IP assignment.

Important Note:

“The server resides in VLAN 10 (HR), while other VLANs access it via router-on-a-stick inter-VLAN routing, demonstrating proper Layer 3 communication in an enterprise network.”

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🌐 Network Topology

Router: 1 (R1)

Switch: 1 Layer 3 Switch (SW1)

PCs: 6 (2 per department)

Server: 1 (DHCP & DNS)

Topology Layout:

🧩 See topology/enterprise-vlan-intervlan-lab.png for network diagram.
Drawio design available at: drawio/enterprise-vlan-intervlan-lab.drawio

🗂️ Device Connection Table

Device	Interface	Connected To	Notes
R1	G0/0	SW1 G0/1	Trunk link for router-on-a-stick
SW1	G0/1	R1 G0/0	Trunk link carrying VLANs 10, 20, 30
SW1	Fa0/1	PC1	HR VLAN 10
SW1	Fa0/2	PC2	HR VLAN 10
SW1	Fa0/3	PC3	IT VLAN 20
SW1	Fa0/4	PC4	IT VLAN 20
SW1	Fa0/5	PC5	Sales VLAN 30
SW1	Fa0/6	PC6	Sales VLAN 30
SW1	Fa0/7	Server	DHCP/DNS Server, trunk or access depending on VLAN assignment

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🧮 IP Addressing Table

Device / Interface	IP Address	Subnet Mask	Default Gateway	VLAN / Notes
Router R1 G0/0.10	192.168.10.1	255.255.255.0	-	VLAN 10 HR (Router-on-a-stick)
Router R1 G0/0.20	192.168.20.1	255.255.255.0	-	VLAN 20 IT
Router R1 G0/0.30	192.168.30.1	255.255.255.0	-	VLAN 30 Sales
PC1 (HR)	192.168.10.10	255.255.255.0	192.168.10.1	VLAN 10
PC2 (HR)	192.168.10.11	255.255.255.0	192.168.10.1	VLAN 10
PC3 (IT)	192.168.20.10	255.255.255.0	192.168.20.1	VLAN 20
PC4 (IT)	192.168.20.11	255.255.255.0	192.168.20.1	VLAN 20
PC5 (Sales)	192.168.30.10	255.255.255.0	192.168.30.1	VLAN 30
PC6 (Sales)	192.168.30.11	255.255.255.0	192.168.30.1	VLAN 30
Server (DHCP/DNS)	192.168.10.100	255.255.255.0	192.168.10.1	Connected to SW1 trunk, serves all VLANs

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🔧 Lab Steps

1. Connect all devices as per topology diagram. → Connect all devices according to the topology diagram.

2. Configure VLANs on the switch.

3. Assign switch ports to VLANs.

4. Configure router-on-a-stick with subinterfaces for each VLAN.

5. Configure DHCP pools on the server or router.

6. Assign PCs to VLANs and enable DHCP. → Assign PCs to their respective VLANs and configure DHCP.

7. Test connectivity between PCs in same VLAN.

8. Test connectivity between PCs in different VLANs (Inter-VLAN routing). → Test inter-VLAN connectivity between PCs in different VLANs.

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💻 Device Configuration

🔌 Switch Configuration

SW1 (Layer 3 Switch)

Below is a snippet of the SW1 config. View the full file below:

SW1(config)#vlan 10
SW1(config-vlan)#name HR
SW1(config-vlan)#vlan 20
SW1(config-vlan)#name IT
SW1(config-vlan)#vlan 30
SW1(config-vlan)#name Sales

View Full Configuration File →

🚦 Router Configuration

Router R1 (Router-on-a-Stick)

Below is a snippet of the R1 config. View the full file below:

R1(config)#interface g0/0
R1(config-if)#no shutdown

! Subinterfaces for VLANs
```text
R1(config)#interface g0/0.10
R1(config-subif)#encapsulation dot1Q 10
R1(config-subif)#ip address 192.168.10.1 255.255.255.0
R1(config-subif)#no shutdown

View Full Configuration File →

📡 DHCP Server Configuration

ON ROUTER (R1)

Below is a snippet of the dhcp config. View the full file below:

R1(config)#
R1(config)#! VLAN 10 HR
R1(config)#ip dhcp pool HR
R1(dhcp-config)#network 192.168.10.0 255.255.255.0
R1(dhcp-config)#default-router 192.168.10.1
R1(dhcp-config)#dns-server 8.8.8.8

View Full Configuration File →

🖧 PC and Server Configuration

Refer to full files:

• PC Configs →

• Server Configs →

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🧾 Verification Commands

1. 🗺️ Topology Screenshot

shows the full lab layout in Packet Tracer.

2. 🔍 VLAN Verification

show vlan brief output on SW1 --> Vlan10,20,30

show vlan brief

3. 🔗 Trunk Verification

Shows show interfaces trunk output, proving the router-to-switch trunk works.

show interfaces trunk

4. ⚙️ Router Subinterfaces / Inter-VLAN Routing

Shows show ip interface brief or show ip route to prove subinterfaces are configured.

show ip interface brief

show ip route

5. 🌐 Connectivity / Ping Test

• Ping between PCs in same VLAN PC 2 to PC1 → “Ping between PCs in the same VLAN (PC2 → PC1)”

- Ping between PCs in different VLANs PC3 to PC6 → “Ping between PCs in different VLANs (PC3 → PC6)”

- Ping server from router R1 to Server1 (VLAN 10)

- Ping server from PCs in different VLANs

Test Summary Table:

Test	Status	Notes
VLAN Configuration	✅ Success	VLANs 10, 20, 30 configured on SW1
Trunk Port	✅ Success	Trunk between SW1 G0/1 and R1 G0/0 verified
Router-on-a-Stick	✅ Success	Subinterfaces configured for all VLANs
DHCP Assignment	✅ Success	PCs received IP addresses automatically
Ping Tests (Intra-VLAN)	✅ Success	PCs in the same VLAN can communicate
Ping Tests (Inter-VLAN)	✅ Success	PCs across VLANs can communicate via router
Server Connectivity	✅ Success	All VLANs can reach the server

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⚡ How to Run Lab

1. Open Cisco Packet Tracer 8.x (recommended).

2. Open the lab file: labs/enterprise-vlan-intervlan-lab.pkt.

3. Follow Lab Steps section above.

4. Verify VLANs, trunking, router-on-a-stick, DHCP and inter-VLAN connectivity.

5. Use the Verification Commands section to confirm correct operation.

6. Optional: Enable Simulation Mode to observe packet flow between VLANS and the Server.

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📁 Folder Structure

enterprise-vlan-intervlan-lab/ │── README.md │── verification.md │── LICENSE │── Learning Outcomes │── Repository Info │ ├── config/ │ ├── router-configs/ │ │ ├── r1.cfg │ │ └── dhcp.cfg │ │ │ ├── switch-configs/ │ │ └── sw1.cfg │ │ │ ├── pc-configs/ │ │ └── pc.txt │ │ │ └── server-configs/ │ └── server.txt │ ├── screenshots/ │ ├── ping_different_vlan.png │ ├── ping_same_vlan.png │ ├── router_ip_route.png │ ├── router_subinterfaces.png │ ├── trunk_port_status.png │ ├── vlan_10_ping_server.png │ ├── vlan_30_ping_server.png │ └── vlan_table_verification.png │ ├── topology/ │ ├── topology_overview.png │ ├── enterprise-vlan-intervlan-lab.png │ └── labs/ └── enterprise-vlan-intervlan-lab.pkt

🧠 Learning Outcomes

After completing this lab, you will be able to:

• Configure VLANs, trunk ports, and router-on-a-stick inter-VLAN routing.

• Assign and verify DHCP-assigned IP addresses across VLANs.”

• Interpret show commands (show vlan brief, show ip interface brief, show ip route, show interfaces trunk) to troubleshoot and verify network configuration.

• Demonstrate network connectivity testing using ping across VLANs and to the server.

• Apply layer 2 and layer 3 network reasoning to solve network issues.

• Develop practical skills relevant to CCNA certification and enterprise network management.

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📂 Repository Info

This project is part of my CCNA Lab Portfolio.
Explore more labs here 👉 @asmymhm

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