Brocade Communications Systems FastIron X Series User Manual

Conguring BGP4 (IPv4)
• BGP4 overview............................................................................................................................................................................................... 351
• Implementation of BGP4............................................................................................................................................................................356
• BGP4 restart.................................................................................................................................................................................................... 356
• Basic conguration and activation for BGP4..................................................................................................................................... 360
• BGP4 parameters..........................................................................................................................................................................................361
• Memory considerations............................................................................................................................................................................... 364
• Basic conguration tasks required for BGP4..................................................................................................................................... 364
• Optional BGP4 conguration tasks........................................................................................................................................................377
• Conguring BGP4 restart........................................................................................................................................................................... 395
• Modifying redistribution parameters.......................................................................................................................................................400
• Filtering............................................................................................................................................................................................................... 402
• Four-byte Autonomous System Numbers (AS4).............................................................................................................................418
• BGP4 AS4 attribute errors.........................................................................................................................................................................423
• Conguring route ap dampening...........................................................................................................................................................424
• Generating traps for BGP4........................................................................................................................................................................ 428
• Conguring BGP4......................................................................................................................................................................................... 428
• Entering and exiting the address family conguration level..........................................................................................................429
• BGP route
reector........................................................................................................................................................................................430
• Specifying a maximum AS path length.................................................................................................................................................432
• BGP4 max-as error messages.................................................................................................................................................................434
• Originating the default route.......................................................................................................................................................................434
• Changing the default metric used for route cost...............................................................................................................................434
• Conguring a static BGP4 network .......................................................................................................................................................435
• Generalized TTL Security Mechanism support.................................................................................................................................438
• Displaying BGP4 information................................................................................................................................................................... 438
• Clearing trac counters............................................................................................................................................................................... 474
• Clearing diagnostic buers.........................................................................................................................................................................475
BGP4 overview
BGP4 is the standard Exterior Gateway Protocol (EGP) used on the Internet to route
trac between Autonomous Systems (AS) and to
maintain loop-free routing. An AS is a collection of networks that share the same routing and administration characteristics. For example,
a corporate Intranet consisting of several networks under common administrative control might be considered an AS. The networks in an
AS can but do not need to run the same routing protocol to be in the same AS, nor do they need to be geographically close.
Devices within an AS can use dierent Interior Gateway Protocols (IGPs) such as RIP and OSPF to communicate with one another.
However, for devices in dierent autonomous systems to communicate, they need to use an EGP. BGP4 is the standard EGP used by
Internet devices and therefore is the EGP implemented on Brocade devices.
This is a simple example of two BGP4 ASs. Each AS contains three BGP4 devices. All of the BGP4 devices within an AS communicate
using IBGP. BGP4 devices communicate with other autonomous systems using EBGP. Notice that each of the devices also is running
an Interior Gateway Protocol (IGP). The devices in AS1 are running OSPF and the devices in AS2 are running RIP. The device can be
congured to redistribute routes among BGP4, RIP, and OSPF. They also can redistribute static routes.
FastIron Ethernet Switch Layer 3 Routing
53-1003627-04 351

Brocade Communications Systems FastIron X Series Specifications

General

Brand	Brocade Communications Systems
Model	FastIron X Series
Category	Switch
Language	English