How To Configure and Verify OSPF On Cisco Routers in GNS3 | Passive-Interface | Step By Step

OSPF (Open Shortest Path First) is a dynamic routing protocol that can be used to exchange routing information between two or more rouiters. OSPF is an Interior Gateway Protocol (IGP) and is used to router traffic between routers within an Autonomous System (AS)
OSPF is the most commonly used IGP in Enterprise Networks beating out EIGRP. You will also see OSPF used a lot in Data Centers and Service Provider environments. It's important to understand how to configure OSPF on your router. It's also important to know how to verify if OSPF has formed between two routers, if a router is advertising a link into OSPF, and what routes a router is learning in OSPF.
Follow these steps to enable OSPF on a Cisco router and advertise it's links:
Step 1- Verify you have basic IP Connectivity between the peers
Step 2 - Enable the OSPF proccess by typing the command router ospf
Step 3 - Enable OSPF on interfaces using the network statement
Step 4 - (Optional) Enable OSPF on an interface at the interface level
Step 5: - (Optional) Manually configure a Router-ID
Step 6 - (Optional) Make an interface passive with the passive-interface command
Show Commands
show ip ospf neighbor - Verify what neighbors you have discovered
show ip ospf interface brief - Verify what links are enabled for OSPF

[@AztecaEl]

You're a genius, man... Thanks !!!

[@romesan2011]

Very well explained

[@faisalak7]

Brilliant thanks