Brocade Communications Systems ICX 7250 series, Руководство по настройке

Страница: 273 / 483

Configuring BGP4 (IPv4)
• BGP4 overview............................................................................................................................................................................................... 273
• Implementation of BGP4............................................................................................................................................................................278
• BGP4 restart.................................................................................................................................................................................................... 278
• Basic configuration and activation for BGP4..................................................................................................................................... 282
• BGP4 parameters.......................................................................................................................................................................................... 283
• Memory considerations............................................................................................................................................................................... 286
• Basic configuration tasks required for BGP4..................................................................................................................................... 286
• Optional BGP4 configuration tasks........................................................................................................................................................299
• Configuring BGP4 restart........................................................................................................................................................................... 316
• Modifying redistribution parameters.......................................................................................................................................................321
• Filtering............................................................................................................................................................................................................... 323
• Four-byte Autonomous System Numbers (AS4).............................................................................................................................339
• BGP4 AS4 attribute errors......................................................................................................................................................................... 344
• Configuring route flap dampening...........................................................................................................................................................344
• Generating traps for BGP4........................................................................................................................................................................ 348
• Configuring BGP4......................................................................................................................................................................................... 349
• Entering and exiting the address family configuration level..........................................................................................................350
• BGP route reflector........................................................................................................................................................................................350
• Specifying a maximum AS path length.................................................................................................................................................353
• BGP4 max-as error messages.................................................................................................................................................................355
• Originating the default route.......................................................................................................................................................................355
• Changing the default metric used for route cost............................................................................................................................... 355
• Configuring a static BGP4 network ....................................................................................................................................................... 356
• Generalized TTL Security Mechanism support.................................................................................................................................359
• Displaying BGP4 information................................................................................................................................................................... 359
• Clearing traffic counters............................................................................................................................................................................... 395
• Clearing diagnostic buffers.........................................................................................................................................................................396
BGP4 overview
BGP4 is the standard Exterior Gateway Protocol (EGP) used on the Internet to route traffic 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 different Interior Gateway Protocols (IGPs) such as RIP and OSPF to communicate with one another.
However, for devices in different 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
configured to redistribute routes among BGP4, RIP, and OSPF. They also can redistribute static routes.
Brocade FastIron Layer 3 Routing Configuration Guide
53-1003903-04 273