How to configure ospf routing protocol using cisco packet. Although basic ospf configuration can be very simple, ospf provides many extra features that can get really complex. The configuration of ospf routing protocol is easy as rip routing. Create separate ospf templates for the two ospf routing types. Configuring route summarization when redistributing routes into ospf 19. But just before we get to configure, lets have an overview of ospf. And, enable specific interfaces using no passive interface. Use the ip ospf authentication command to specify this password. Areas have to be connected to the backbone area but if they arent we can fix it with a virtual link.
Ospf configuration step by step guide this tutorial explains how to configure ospf routing protocol step by step with practical example in packet tracer. View a summary of the ospf linkstate database entries. Ospf is commonly used in large service provider networks or large financial institutions. A number of different cisco ios ospf configuration commands are available, but at its most basic, ospf configuration uses three commands. How to configure ospf stub area previously i explained the different ospf special area types called stub areas. Open shortest path first ospf routing protocol dummies. Ospf is perhaps the most widely used interior gateway protocol igp in large enterprise networks. Configuration dospfv2 et ospfv3 en cisco ios cisco.
Now it is time to go deep and combine virtual link, lsa types and etc. For ospf configuration information and examples, refer to the configuring ospf chapter. One of the type im having confusion is pointtomultipoint. This tutorial will give you an easy guide of configuring basic ospf on a cisco router. This module describes how to configure open shortest path first ospf. How to configure ospf on cisco routers with example commands. Configure passive interface for the user vlans and stubnetworks. Configure passive interface default under ospf routing process. You can see that r1 has learned about the network 192.
This type of stub area is an extension to ospf created by cisco. Cisco sdwan documentation is now accessible via the cisco product support portal. Download cisco ccnp routing pdf study guide snabay networking. In our example, we will examine the figure below deeply. Router ids must be unique to prevent unintended ospf database problems. My cisco nexus configured with hsrp with all the svis on 192. To configure a netowork for ospf properly there are some steps. I will give you some basic overview about ospf and then will provide the details of these configuration by practically configuring a lab. We talked about ospf basics and made an ospf configuration for beginners on our course.
Here is the configuration to enable md5 authentication. The idea is the same but some of the commands are different. To do so, first we need to enable ospf in our router. This time, well take a look how you can configure multi area ospf. How to configure ospfv3 ipv6 routing in cisco routers. This chapter focuses on a number of objectives falling under the ccnp routing principles. I dont know about you but i love my navigation system. The task is to optimize ospf routing, which creates the need to design and configure multiarea ospf. Jun 28, 2017 it is time to take a look to configuring ospf open shortest path first with an ospf configuration example. Ospf can scale to the largest lans but can also start out small. Configuring route summarization when redistributing routes into ospf 23.
Ospf interarea route summarization cisco community. This of course leads to more complexity in the configuration and troubleshooting of ospf networks. Ospf employs a hierarchical network design using areas. In this article we will see how to configure ospf step by step. Ospf is link state routing protocol that works on the concept of areas. The main difference here is that a linkedstate protocol does not send its routing table in the form of updates, but only shared its connectivity configuration. Once you are in the router ospf configuration submode, configure the lan network 172. For protocolindependentfeaturesthat work with ospf, see the configuring ip routing protocolindependent. Home downloads download cisco ccnp routing pdf study guide. Open shortest path first ospf is a linkstate routing protocol, rather than a distance vector protocol. Since these kinds of posts are useful as a reference for many people, i have decided to create also a cisco router commands cheat sheet with the most useful and the most frequently used command line interface. First you need to specify the area 1 where we need the virtuallink which is area 1 in my example.
The ospf network command uses a combination of networkaddress and wildcardmask. We configure the virtuallink between abrs and we use the area virtuallink command. In this lesson ill explain the basics of ospf to you and you will learn how and why it works. Ospf is an interior gateway protocol igp developed by the ospf working group of the internet engineering task force ietf.
Ospf configuration, the router sends a notification message to the console stating that a neighbor relationship with another ospf router has been established. This keeps track of external routes injected by exterior protocols such as bgp. If you remember the ospf configuration for ipv4, the networks are added to the ospf process with network statements under ospf router configuration mode. If you studied cisco s ccna you have learned that when you use ospf all the areas have to be directly connected to the backbone area. Link state routing protocols advertise the state of their links. Basic ospf configuration for internal router abr and asbrs 44. Cisco ios router configuration commands cheat sheet pdf. The process id number is a locally significant process identification number and this does not need to match neighboring routers. The cost was configured with the ip ospf cost interface configuration command. For protocolindependent features that include ospf, see the chapter configuring ip routing. Here in this lesson, we will learn basic ospfv3 configuration in a small network consisting of three cisco routers, three layer 2 switches and three computers. In ospfv3, the configuration is entirely different.
The router id can be used to break a tie in the election process. Cisco router configuration commands cli cheat sheet. Ospf will form neighbor relationships with adjacent routers in the same area. In 2008 free ccna workbook originally started as a sharable pdf but quickly evolved into the largest ccna training lab website.
Define area 9 as a totally stubby area area 9 stub nosummary. In a previous lesson i demonstrated how to configure plain text authentication for ospf. Ospf open shortest path first is an open standard routing protocol, meaning any vendor like cisco, juniper, brocade can implement its features. Ospf uses a routing metric of cost that in ciscos implementation is based mainly on the bandwidth of a link. Understanding basic open shortest path first ospf routing principles not only applies to the ccnp certification but to all cisco based certifications. Jun 22, 2017 in this article we will make an example for advanced ospf configuration. Cisco any yes yes 1040 cisco full mesh no yes 1040 cisco pointtopoint area 0 a backbone area 9. Scenario international travel agency ita maintains a complex ospf environment. Audience the cisco ios documentation set is intended for users who configure and maintain cisco networking devices such as routers and switches but who may not be familiar with the configuration and.
Ospf configuration step by step guide computernetworkingnotes. Ospf adheres to the following link state characteristics. Ospf open shortest path first protocol is a wellknow routing protocol that is widely used today. When a link state router begins operating on a network link, information associated with that logical network is added to its local link state database lsdb.
Configure the interfaces on the r1, r2, and r3 routers with the ip addresses from the table under the topology diagram. While ospf can be complex to configure, its basic configuration isnt difficult. Ospf can be used for serviceside routing, to provide reachability to networks at the local site, and it can be used for transportside routing, to enable communication between the vedge router and other viptela devices when the router is not directly connected to the wan cloud. Routing configuration guide, cisco ios xe release 17. Download this cisco router configuration commands cheat sheet in pdf format at the end of this post herethe most important cli commands are included that will help you in the field. Cisco ios documentation describes the tasks and commands available to configure and maintain cisco networking devices. If im correct, this network type emulates a pointtopoint connection where no drbdr is required and no need to define manual neighbors in order to establish the adjacencies between ospf routers in nbma network like framerelay. On any pointtomultipoint interface broadcast or not, the cisco ios xe software assumed that the cost to each neighbor was equal. The open shortest path first ospf protocol, defined in rfc 2328, is an interior gateway protocol used to distribute routing information within a single autonomous system. Ospf configuration guide americas headquarters cisco systems, inc. Routers will exchange pieces of information called lsas link state advertisement in order to build a complete topology database which we call the lsdb link state database.
This article is the fourth in a series of articles covering the basics of cisco networking. This article is about the ospf configuration in packet tracer. I have this setup with a hybrid of equipments from cisco and ubiquiti edge routers and vyos. For protocolindependent features, see the chapter configuring ip routing protocolindependent. The retooled cisco certified network associate ccna exam has been updated to reflect the latest technologies and job roles. Just two routers in the same area, nothing special. Jun 11, 2019 this article is about the ospf configuration in packet tracer. Authentication of peers is important as well, and you should use routemaps for. The ospf routerid is used to identify a specific device within an ospf database. In reality, the bandwidth to each neighbor is different, so the cost should differ. Ospf open shortest path first is a popular linkstate routing protocol. Create an ospf feature template to configure ospf parameters, as described in this article.
This paper examines how ospf works and how it can be used to design and build large and complicated networks. Im a trainee in networks, and i had an exercice of routing protocols and a static route ospf, eigrp, rip, et static. Learn ospf configuration commands, ospf show commands, ospf network configuration process id, network id, wild card mask and area number and ospf routing in detail. Cisco ospf configuration commands for checking adjacency, dr bdr election and stub area. Second step is to configure the ospf router id of the other abr. Configure the ospf autocost reference bandwidth through out the ospf domain to higher than the highest bandwidth link in the network. Hi everyone, im trying to understand ospf network types. For ospf configuration information and ex amples, refer to the con figuring ospf chapter of the network protocols configuration guide, part 1. Ospf is a classless routing protocol that supports vlsm and cidr, and uses the shortest path first spf algorithm to calculate the best path to a network. Ospf commands use the commands in this chapter to configure and monitor the open shortest path first ospf routing protocol. How to configure basic ospf by brandon carroll in networking on july 26, 2017, 12.
We start with the definition of router id, and then continue on network and passive interface definition. In my introduction on ospf i explained why we sometimes use multiple areas for ospf and in our configuration example, i showed you how to configure ospf for a single area. I tried to do the redistribution between the lans but it doesnt work for me, my ping command fails, i. Configuring ospf ospf configuration task list ipc216 cisco ios ip configuration guide virtual linksvirtual links are supported. To create a scalable cisco ospf configuration, you need to follow the best practices. Basic ospf configuration for internal router abr and asbrs 52. How to configure ospf routing protocol using cisco packet tracer. By collecting connectivity information from all of the devices on the network, ospf. Ospf is a standard internal gateway protocol igp that is used by many different types and sizes of companies. This lab will discuss and demonstrate the configuration and verification of the ospf routerid. Basic ospf configuration for internal router abr and asbrs 41.
Ospf configuration in packet tracer computer networking. Jul 26, 2017 how to configure basic ospf by brandon carroll in networking on july 26, 2017, 12. In the next series of lessons i will show you the configuration of each ospf stub type. All routes marked with the character o are ospf routes. Authenticate adjacencies with md5 ip ospf authentication messagedigest. For example, here is the output of the command on r1. The revised exam tests networking professionals understanding of foundational and, at a basic level, emerging topics. Download cisco ccnp routing pdf study guide snabay.
Basic ospf configuration for internal router abr and asbrs 40. The open shortest path first ospf is a routing protocol for wide area networks and enterprise network. Simple ospf network need to create ospf routing process router configuration command router ospf specify the network running ospf should also specify the area 25. This tutorial explains how to configure ospf routing protocol step by step with practical example in packet tracer. This article takes a look at the configuration of open shortest path first ospf. Today we will discuss how to configure ospf in cisco routers. Ospf is standardsbased which means it is available on routers by cisco as well as other vendors, making it a vendorneutral routing protocol. Cisco ospf configuration according to best practices. Feature information for configuring ospf ttl security check and ospf graceful. Ospf allows for the transfer and tagging of external routes injected into an autonomous system. Configuring multiarea ospf objective in this lab configure a multiarea ospf operation, interarea summarization, external route summarization, and default routing. In a previous post, i have published a cisco switch commands cheat sheet tutorial.
A concrete understanding of how ospf routing works is fundamental for any small or large network. Ospf configuration in packet tracer lab with pdf networking. Ospf uses the dijkstra shortest path first algorithm to determine the shortest path. Ospf configuration guide cisco ios xe 3se catalyst 3850. Configure ospf area parameters p1c112 network protocols configuration guide, part 1 on any pointtomultipoint interf ace broadcast or not, the cisco io.
The router ospf processid command is the beginning of any cisco ios ospf configuration. About ospf open shortest path first ospf is one of the dynamic routing protocols amongst others. Ospf p art 1 protocol header type attributes algorithm metric linkstate dijkstra cost bandwidth ad. Keep this in mindyou need to configure the ospf router id and not the ip address of the abr. How to configure ospf in cisco router letsconfig from basic. Ospf open shortest path first ospf is a standardized linkstate routing protocol, designed to scale efficiently to support larger networks. Optional md5 authentication configured ip ospf authentication messagedigest ip ospf messagedigestkey 1 md5 foobar. Ospf was designed expressly for ip networks and it supports ip subnetting and tagging of externally derived routing information. Ospf network type nbma nonbroadcast multiple access uses only unicast communications, so it is the preferred way of ospf configuration in situations where multicast addressing is not possible or desirable for some reasons.
Ospf configuration task list ospf typically requires coordination among many internal routers. In this document we discussed about route summarization between the areas. For basic ospf configuration, the followin scenario will be a good example. Open shortest path first ospf is a routing protocol developed by internet engineering task force ietf.