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Free CCNA | Configuring OSPF (1) | Day 26 Lab | CCNA 200-301 Complete Course

2 min read 5 months ago

Published on Nov 25, 2025 This response is partially generated with the help of AI. It may contain inaccuracies.

Table of Contents

Introduction

In this tutorial, you will learn how to configure Open Shortest Path First (OSPF) on Cisco devices, focusing on key concepts like passive interfaces and advertising a default route using the command default-information originate. This guide is designed for those preparing for the CCNA 200-301 exam and provides practical, hands-on experience.

Step 1: Access the Cisco Device

Use terminal emulation software (like PuTTY or Tera Term) to connect to your Cisco router.
Ensure you have the necessary privileges to execute configuration commands.
Enter privileged EXEC mode by typing:
```
enable
```

Step 2: Enter Global Configuration Mode

To begin configuring OSPF, you need to enter global configuration mode. Type:
```
configure terminal
```

Step 3: Configure OSPF

Start the OSPF configuration by using the following command, replacing 1 with your OSPF process ID:
```
router ospf 1
```
Specify the network you want to include in OSPF. For example, if you want to include the network 192.168.1.0/24, use:
```
network 192.168.1.0 0.0.0.255 area 0
```

Step 4: Set Up Passive Interfaces

To make an interface passive (stop sending OSPF hello packets), exit to global configuration mode and enter the interface configuration:
```
interface GigabitEthernet0/0
ip ospf passive-interface
```
Repeat this for any interfaces you want to set as passive.

Step 5: Advertise a Default Route

To advertise a default route in OSPF, return to the OSPF configuration mode and enter:
```
default-information originate
```
This command will allow routers in the OSPF area to learn about the default route (0.0.0.0/0).

Step 6: Verify OSPF Configuration

Use the following command to check OSPF neighbors and verify that OSPF is functioning correctly:
```
show ip ospf neighbor
```
To view the OSPF routing table, use:
```
show ip route ospf
```

Conclusion

In this tutorial, you successfully configured OSPF on a Cisco router, set passive interfaces, and advertised a default route. As you continue your CCNA preparation, practice these configurations in a lab environment to build your confidence and skills. For further learning, consider exploring advanced OSPF features or other routing protocols.

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