Configuring Bgp - Cisco 3750G - Catalyst Integrated Wireless LAN Controller Configuration Manual

Chapter 35 Configuring IP Unicast Routing
Table 35-8 IP EIGRP Clear and Show Commands (continued)
Command
show ip eigrp topology [autonomous-system-number] |
[[ip-address] mask]]
show ip eigrp traffic [autonomous-system-number]

Configuring BGP

The Border Gateway Protocol (BGP) is an exterior gateway protocol used to set up an interdomain
routing system that guarantees the loop-free exchange of routing information between autonomous
systems. Autonomous systems are made up of routers that operate under the same administration and
that run Interior Gateway Protocols (IGPs), such as RIP or OSPF, within their boundaries and that
interconnect by using an Exterior Gateway Protocol (EGP). BGP Version 4 is the standard EGP for
interdomain routing in the Internet. The protocol is defined in RFCs 1163, 1267, and 1771. You can find
detailed information about BGP in Internet Routing Architectures, published by Cisco Press, and in the
"Configuring BGP" chapter in the Cisco IP and IP Routing Configuration Guide.
For details about BGP commands and keywords, see the "IP Routing Protocols" part of the Cisco IOS
IP Command Reference, Volume 2 of 3: Routing Protocols, Release 12.2. For a list of BGP commands
that are visible but not supported by the switch, see
Cisco IOS Release 12.2(35)SE."
Routers that belong to the same autonomous system (AS) and that exchange BGP updates run internal
BGP (IBGP), and routers that belong to different autonomous systems and that exchange BGP updates
run external BGP (EBGP). Most configuration commands are the same for configuring EBGP and IBGP.
The difference is that the routing updates are exchanged either between autonomous systems (EBGP) or
within an AS (IBGP).
Figure 35-5
AS 100
Router B
175.220.212.1
Before exchanging information with an external AS, BGP ensures that networks within the AS can be
reached by defining internal BGP peering among routers within the AS and by redistributing BGP
routing information to IGPs that run within the AS, such as IGRP and OSPF.
OL-8550-02
Figure 35-5
EBGP , IBGP , and Multiple Autonomous Systems
Router A
129.213.1.2
EBGP
129.213.1.1
Purpose
Display the EIGRP topology table for a given process.
Display the number of packets sent and received for all or a
specified EIGRP process.
Appendix D, "Unsupported Commands in
shows a network that is running both EBGP and IBGP.
Router D
192.208.10.2
IBGP
175.220.1.2
Catalyst 3750 Switch Software Configuration Guide
AS 300
192.208.10.1
EBGP
Router C
AS 200
Configuring BGP
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