Static Routing — Practical + Interview Guide

🌐 Static Routing — Practical + Interview Guide

📌 What is Static Routing?

Static routing is a method where routes are manually configured on routers to define how packets should reach different networks.

👉 Simple:

“Router ko manually batate hain traffic kahan bhejna hai.”

🎯 What You Will Learn

• Communication between different networks
• How routers forward packets
• Real-world routing logic

🧪 Lab Setup (in Cisco Packet Tracer)

🔹 Topology

PC1 --- Router1--- Router2 --- PC2

Lab Topology & IP Addressing Plan

Step 1 — Build topology in Packet Tracer

• Drag 2 x Router 2911 and 2 x PC
• Connect PC1 → Router1 with Copper Straight-Through
• Connect Router1 → Router2 with Copper Cross-Over (or Serial DCE)
• Connect Router2 → PC2 with Copper Straight-Through

Step 2 — Configure IP addresses

Router 1:

Router> enable
Router# configure terminal
Router(config)# hostname R1
R1(config)# interface GigabitEthernet 0/0
R1(config-if)# ip address 192.168.1.1 255.255.255.0
R1(config-if)# no shutdown
R1(config-if)# exit
R1(config)# interface GigabitEthernet 0/1
R1(config-if)# ip address 10.0.0.1 255.255.255.252
R1(config-if)# no shutdown
R1(config-if)# end

Router 2:

Router> enable
Router# configure terminal
Router(config)# hostname R2
R2(config)# interface GigabitEthernet 0/0
R2(config-if)# ip address 10.0.0.2 255.255.255.252
R2(config-if)# no shutdown
R2(config-if)# exit
R2(config)# interface GigabitEthernet 0/1
R2(config-if)# ip address 192.168.3.1 255.255.255.0
R2(config-if)# no shutdown
R2(config-if)# end

Step 3 — Add Static Routes ⭐ (Most important!)

ip route [destination network] [subnet mask] [next-hop IP]
On Router 1 — tell it how to reach Network 3:
R1(config)# ip route 192.168.3.0 255.255.255.0 10.0.0.2

On Router 2 — tell it how to reach Network 1:
R2(config)# ip route 192.168.1.0 255.255.255.0 10.0.0.1

Step 4 — Configure PCs

On PC1 → Desktop → IP Configuration:

IP: 192.168.1.10, Mask: 255.255.255.0, Gateway: 192.168.1.1

On PC2 → Desktop → IP Configuration:

IP: 192.168.3.10, Mask: 255.255.255.0, Gateway: 192.168.3.1

Step 5 — Test with Ping

• On PC1 → Desktop → Command Prompt:
• ping 192.168.3.10
• You should see 4 replies ✅

Might be possible first time when you will ping it will only 2 replies came and others packets loss but second time if you try definitely ping successfully and winner winner !!

Verify on Router

R1# show ip route

R1# show running-config

Common mistakes to avoid:

• Forgetting no shutdown on interfaces
• Wrong next-hop IP (must be the directly connected neighbor's IP)
• Missing the return route (both routers need static routes!)
• Wrong subnet mask in the ip route command