user manual
Table Of Contents
- Cisco Content Services Switch Routing and Bridging Configuration Guide
- Contents
- Preface
- Configuring Interfaces and Circuits
- Interface and Circuit Overview
- Configuring Interfaces
- Configuring an Interface
- Entering a Description for the Interface
- Configuring Interface Duplex and Speed
- Setting Interface Maximum Idle Time
- Bridging an Interface to a VLAN
- Specifying VLAN Trunking for an Interface
- Configuring Spanning-Tree Bridging for a VLAN or a Trunked Interface
- Configuring Port Fast on an Interface
- Showing Interface Configurations
- Shutting Down an Interface
- Shutting Down All Interfaces
- Restarting an Interface
- Restarting All Interfaces
- Configuring Circuits
- Configuring RIP for an IP Interface
- Configuring the Switched Port Analyzer Feature
- Configuring Spanning-Tree Bridging for the CSS
- CSS Spanning-Tree Bridging Quick Start
- Configuring Spanning-Tree Bridge Aging-Time
- Configuring Spanning-Tree Bridge Forward-Time
- Configuring Spanning-Tree Bridge Hello-Time
- Configuring Spanning-Tree Bridge Max-Age
- Configuring Spanning-Tree Bridge Priority
- Disabling Bridge Spanning-Tree
- Showing Bridge Configurations
- Configuring Open Shortest Path First (OSPF)
- OSPF Overview
- CSS OSPF Configuration Quick Start
- Configuring OSPF on the CSS
- Configuring OSPF on a CSS IP Interface
- Showing OSPF Information
- OSPF Configuration in a Startup-Configuration File
- Configuring the Address Resolution Protocol
- Configuring Routing Information Protocol
- Configuring the Internet Protocol
- IP Configuration Quick Start
- Configuring an IP Route
- Disabling an Implicit Service for the Static Route Next Hop
- Configuring an IP Source Route
- Configuring the IP Record Route
- Configuring Box-to-Box Redundancy
- Configuring IP Equal-Cost Multipath
- Forwarding IP Subnet Broadcast Addressed Frames
- Configuring IP Unconditional Bridging
- Configuring IP Opportunistic Layer 3 Forwarding
- Showing IP Configuration Information
- Configuring the Cisco Discovery Protocol
- Configuring the DHCP Relay Agent
- Index
Chapter 3 Configuring Open Shortest Path First (OSPF)
OSPF Overview
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Cisco Content Services Switch Routing and Bridging Configuration Guide
OL-4580-01
OSPF Overview
OSPF is a link-state routing protocol that:
• Provides network topology discovery within a group of routers and networks
called an autonomous system (AS)
• Calculates the shortest path to destinations within the AS
As a link-state protocol, OSPF routers flood any change in routing information
throughout the network. This action differs from a distance vector protocol, such
as RIP, which periodically exchanges routing information only with neighboring
devices.
Within an AS, each OSPF router builds and synchronizes a database of the AS
network topology. The routers synchronize their databases by requesting
information from other AS routers. Each router sends its information as link-state
advertisements (LSAs) that include information about the state of each router and
link in the AS. A link is an interface on the router. The state of the link is the
description of the interface, including the router’s IP address and subnet mask,
and its relationship to the neighboring router.
Then, the router uses its database and the Shortest Path First (SPF) algorithm to
calculate the shortest path to every destination in the AS and stores this
information in a dynamic table. When changes occur, the router calculates new
paths.
The CSS, operating as an OSPF router, provides:
• Intra-area route support for routing in a single area between other OSPF
routers
• Inter-area route support for routing between multiple OSPF areas
• Route summarization between areas as an Area Border Router (ABR)
• Stub area and AS boundary router support
• Redistribution of local, RIP, static, and firewall routes into an OSPF domain
• Advertisement of VIP addresses for content as AS external routes
• Simple authentication
This section includes the following topics:
• OSPF Routing Hierarchy
• Link-State Databases