Steps For Configuring Routing - Cisco WS-C3560-48PS-S Software Configuration Manual

Chapter 30 Configuring IP Unicast Routing
Dynamic routing protocols are used by routers to dynamically calculate the best route for forwarding
traffic. There are two types of dynamic routing protocols:
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Distance-vector protocols supported by the Catalyst 3560 switch are Routing Information Protocol
(RIP), which uses a single distance metric (cost) to determine the best path; Interior Gateway Routing
Protocol (IGRP), which uses a series of metrics; and Border Gateway Protocol (BGP), which adds a path
vector mechanism. The switch also supports the Open Shortest Path First (OSPF) link-state protocol and
Enhanced IGRP (EIGRP), which adds some link-state routing features to traditional IGRP to improve
efficiency.
The supported protocols are determined by the software running on the switch. If the switch is running
Note
the SMI, only default routing, static routing and RIP are supported. All other routing protocols require
the EMI.

Steps for Configuring Routing

By default, IP routing is disabled on the switch, and you must enable it before routing can take place.
For detailed IP routing configuration information, refer to the Cisco IOS IP and IP Routing
Configuration Guide for Release 12.1.
In the following procedures, the specified interface must be one of these Layer 3 interfaces:
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A Layer 3 switch can have an IP address assigned to each routed port and SVI. The number of routed
Note
ports and SVIs that you can configure is not limited by software. However, the interrelationship between
this number and the number and volume of features being implemented might have an impact on CPU
utilization because of hardware limitations. To optimize system memory for routing, use the sdm prefer
routing global configuration command.
All Layer 3 interfaces on which routing will occur must have IP addresses assigned to them. See the
"Assigning IP Addresses to Network Interfaces" section on page
78-16156-01
Routers using distance-vector protocols maintain routing tables with distance values of networked
resources, and periodically pass these tables to their neighbors. Distance-vector protocols use one
or a series of metrics for calculating the best routes. These protocols are easy to configure and use.
Routers using link-state protocols maintain a complex database of network topology, based on the
exchange of link-state advertisements (LSAs) between routers. LSAs are triggered by an event in
the network, which speeds up the convergence time or time required to respond to these changes.
Link-state protocols respond quickly to topology changes, but require greater bandwidth and more
resources than distance-vector protocols.
A routed port: a physical port configured as a Layer 3 port by using the no switchport interface
configuration command.
A switch virtual interface (SVI): a VLAN interface created by using the interface vlan vlan_id
global configuration command and by default a Layer 3 interface.
An EtherChannel port channel in Layer 3 mode: a port-channel logical interface created by using
the interface port-channel port-channel-number global configuration command and binding the
Ethernet interface into the channel group. For more information, see the
EtherChannels" section on page 29-12.
Catalyst 3560 Switch Software Configuration Guide
Steps for Configuring Routing
"Configuring Layer 3
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