Alcatel Carrier Internetworking Solutions 060187-10 REV D 1 Configuring OSPF

OmniSwitch 6600 Family Advanced Routing Configuration Guide March 2005 page 1-1

1 Configuring OSPF

Open Shortest Path First routing (OSPF) is a shortest path first (SPF), or link state, protocol. OSPF is an

interior gateway protocol (IGP) that distributes routing information between routers in a single Autono-

mous System (AS). OSPF chooses the least-cost path as the best path. OSPF is suitable for complex

networks with large numbers of routers since it provides faster convergence where multiple flows to a

single destination can be forwarded on one or more interfaces simultaneously.

In This Chapter

This chapter describes the basic components of OSPF and how to configure them through the Command

Line Interface (CLI). CLI commands are used in the configuration examples; for more details about the

syntax of commands, see the OmniSwitch CLI Reference Guide.

Configuration procedures described in this chapter include:

•Loading and enabling OSPF. See “Activating OSPF” on page 1-17.

•Creating OSPF areas. See “Creating an Area” on page1-18.

•Creating OSPF interfaces. See “Creating OSPF Interfaces” on page 1-22.

•Creating virtual links. See “Creating Virtual Links” on page1-25

•Using redistribution policies and filters. See “Enabling Redistribution” on page1-26

For information on creating and managing VLANs, see “Configuring VLANs” in the OmniSwitch 6600

Family Network Configuration Guide.

Contents

Main Page Contents Page About This Guide Supported Platforms Unsupported Platforms Who Should Read this Manual? When Should I Read this Manual? What is in this Manual? What is Not in this Manual? How is the Information Organized? Documentation Roadmap Stage 1: Using the Switch for the First Time Stage 2: Gaining Familiarity with Basic Switch Functions Stage 3: Integrating the Switch Into a Network Anytime Related Documentation User Manual CD Technical Support 1 Configuring OSPF In This Chapter OSPF Specifications OSPF Defaults Table Enables OSPF. Enables an area. Enables an interface. Sets the overflow interval value. OSPF Quick Steps 9Assign the OSPF interface to the area and the backbone using the ip ospf interface area command. For example: or 10Enable the OSPF interfaces using the ip ospf interface status command. For example: or 11You can now display the router OSPF settings by using the show ip ospf command. The output gener- 12You can display OSPF area settings using the show ip ospf area command. For example: 13You can display OSPF interface settings using the show ip ospf interface command. For example: OSPF Overview OSPF Areas Classification of Routers Virtual Links Stub Areas OSPF Stub Area Not-So-Stubby-Areas Totally Stubby Areas Equal Cost Multi-Path (ECMP) Routing Non Broadcast OSPF Routing Graceful Restart on Stacks with Redundant Switches Page Configuring OSPF Preparing the Network for OSPF Activating OSPF Loading the Software Enabling OSPF Removing OSPF from Memory Creating an OSPF Area Creating an Area Enabling an Area Specifying an Area Type Enabling and Disabling Summarization Displaying Area Status Deleting an Area Configuring Stub Area Default Metrics Setting Area Ranges Configuring a Totally Stubby Area 1Enter the following commands on Router B: 2Enter the following on Router A: Creating OSPF Interfaces Creating an Interface Assigning an Interface to an Area Activating an Interface Interface Authentication Modifying Interface Parameters belonging to this interface. Creating Virtual Links Creating a Virtual Link Modifying Virtual Link Parameters Creating Redistribution Policies and Filters Specifying an Autonomous System Boundary Router Enabling Redistribution Creating A Redistribution Policy Creating a Redistribution Filter Page Configuring Router Capabilities Configuring Static Neighbors Configuring Redundant Switches in a Stack for Graceful Restart OSPF Application Example Three Area OSPF Network Step 1: Prepare the Routers Page Step 2: Enable OSPF Step 3: Create and Enable the Areas and Backbone Step 4: Create, Enable, and Assign Interfaces Page Step 5: Examine the Network Verifying OSPF Configuration A Software License and Copyright Statements Alcatel License Agreement ALCATEL INTERNETWORKING, INC. (AII) SOFTWARE LICENSE AGREEMENT Page Page Third Party Licenses and Notices A.Booting and Debugging Non-Proprietary Software B. The OpenLDAP Public License: Version 2.4, 8 December 2000 C. Linux D. GNU GENERAL PUBLIC LICENSE: Version 2, June 1991 Preamble GNU GENERAL PUBLIC LICENSE TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION Page Page Page Appendix: How to Apply These Terms to Your New Programs E. University of California F. Carnegie-Mellon University G.Random.c H.Apptitude, Inc. I. Agranat J. RSA Security Inc. K. Sun Microsystems, Inc. L. Wind River Systems, Inc. M.Network Time Protocol Version 4 Index A B D E O R S T V