Dell S4820T User Manual

Sessions and Peers............................................................................................................................199
Establish a Session......................................................................................................................200
Route Reflectors................................................................................................................................201
BGP Attributes...................................................................................................................................202
Best Path Selection Criteria........................................................................................................202
Weight......................................................................................................................................... 204
Local Preference.........................................................................................................................205
Multi-Exit Discriminators (MEDs)................................................................................................205
Origin...........................................................................................................................................206
AS Path.........................................................................................................................................207
Next Hop..................................................................................................................................... 207
Multiprotocol BGP............................................................................................................................208
Implement BGP with Dell Networking OS...................................................................................... 208
Additional Path (Add-Path) Support...........................................................................................208
Advertise IGP Cost as MED for Redistributed Routes................................................................209
Ignore Router-ID for Some Best-Path Calculations..................................................................210
Four-Byte AS Numbers............................................................................................................... 210
AS4 Number Representation...................................................................................................... 210
AS Number Migration.................................................................................................................. 212
BGP4 Management Information Base (MIB).............................................................................. 214
Important Points to Remember..................................................................................................214
Configuration Information................................................................................................................215
BGP Configuration............................................................................................................................ 215
Enabling BGP...............................................................................................................................216
Configuring AS4 Number Representations............................................................................... 220
Configuring Peer Groups............................................................................................................222
Configuring BGP Fast Fall-Over................................................................................................. 224
Configuring Passive Peering.......................................................................................................226
Maintaining Existing AS Numbers During an AS Migration........................................................227
Allowing an AS Number to Appear in its Own AS Path............................................................. 228
Enabling Graceful Restart........................................................................................................... 229
Enabling Neighbor Graceful Restart.......................................................................................... 230
Filtering on an AS-Path Attribute................................................................................................ 231
Regular Expressions as Filters.....................................................................................................232
Redistributing Routes..................................................................................................................234
Enabling Additional Paths........................................................................................................... 234
Configuring IP Community Lists................................................................................................ 235
Configuring an IP Extended Community List............................................................................ 236
Filtering Routes with Community Lists.......................................................................................237
Manipulating the COMMUNITY Attribute...................................................................................238
Changing MED Attributes...........................................................................................................240
Changing the LOCAL_PREFERENCE Attribute..........................................................................240
8

Dell S4820T Specifications

General

Brand	Dell
Model	S4820T
Category	Switch
Language	English