how to configured three routers static ip address with serial port command prompt 2026
How to Configure Three Routers with Static IP Address Using Serial Port (Command Line) – 2026 Guide
Website: https://sreekrishnatechbloganantapur2026.blogspot.com/
Email: pgollabala@gmail.com
Introduction
In networking, configuring multiple routers with static IP addresses using serial connections is a fundamental skill, especially for students, network engineers, and IT professionals. This guide explains how to configure three routers using command line (CLI) with serial ports step by step.
This tutorial is designed for beginners and professionals who want a clear understanding of router configuration using static routing.
Network Topology
We will configure 3 routers connected using serial cables:
Router1 -------- Router2 -------- Router3
IP Address Plan
| Device | Interface | IP Address | Subnet Mask |
|---|---|---|---|
| Router1 | S0/0/0 | 192.168.1.1 | 255.255.255.252 |
| Router2 | S0/0/0 | 192.168.1.2 | 255.255.255.252 |
| Router2 | S0/0/1 | 192.168.2.1 | 255.255.255.252 |
| Router3 | S0/0/0 | 192.168.2.2 | 255.255.255.252 |
Requirements
3 Routers (Cisco or simulator like Packet Tracer)
Serial cables (DCE/DTE)
Console cable
Basic knowledge of CLI
Step 1: Basic Configuration (All Routers)
Enter global configuration mode:
enable
configure terminal
Set hostname:
Router1
hostname R1
Router2
hostname R2
Router3
hostname R3
Step 2: Configure Serial Interfaces
Configure Router1
interface serial 0/0/0
ip address 192.168.1.1 255.255.255.252
clock rate 64000
no shutdown
exit
Configure Router2
interface serial 0/0/0
ip address 192.168.1.2 255.255.255.252
no shutdown
exit
interface serial 0/0/1
ip address 192.168.2.1 255.255.255.252
clock rate 64000
no shutdown
exit
Configure Router3
interface serial 0/0/0
ip address 192.168.2.2 255.255.255.252
no shutdown
exit
Important Note
Apply clock rate only on DCE side
Use command to check DCE:
show controllers serial 0/0/0
Step 3: Configure Static Routing
Now configure routing so all routers can communicate.
Router1 Routing
ip route 192.168.2.0 255.255.255.252 192.168.1.2
Router2 Routing
ip route 192.168.1.0 255.255.255.252 192.168.1.1
ip route 192.168.2.0 255.255.255.252 192.168.2.2
Router3 Routing
ip route 192.168.1.0 255.255.255.252 192.168.2.1
Step 4: Verify Configuration
Use the following commands:
Check Interfaces
show ip interface brief
Check Routing Table
show ip route
Test Connectivity
ping 192.168.2.2
ping 192.168.1.1
Step 5: Save Configuration
write memory
OR
copy running-config startup-config
Troubleshooting Tips
If the network is not working:
Check cables are properly connected
Ensure interfaces are not shutdown
Verify IP addresses
Check routing configuration
Confirm clock rate on DCE side
Use
pingandtraceroutecommands
Advantages of Static Routing
Simple to configure
No CPU overhead
More secure (no routing updates)
Best for small networks
Disadvantages
Not scalable
Manual configuration required
No automatic updates
Conclusion
Configuring three routers with static IP addresses using serial ports is an essential networking skill. By following this guide, you can easily set up communication between routers using CLI commands.
This method is widely used in labs, certifications like CCNA, and small network environments.
About Us
Sree Krishna Tech Blog provides tutorials on networking, software, blogging, and online earning methods. Stay connected for more updates.
🌐 Website: https://sreekrishnatechbloganantapur2026.blogspot.com/
📧 Email: pgollabala@gmail.com
If you want, I can also create:
✅ Diagram image for this setup
✅ Packet Tracer (.pkt) file
✅ YouTube script for this topic
✅ Telugu version for your blog
Just tell me 👍