Setup Guide

Changing a BGP router ID
BGP uses the congured router ID to identify the devices in the network.
By default, the router ID is the highest IP address of the Loopback interface. If no Loopback interfaces are congured, the highest IP
address of a physical interface on the router is used as the BGP router ID. To change the default BGP router ID, use the following
command.
• Change the BGP router ID of a BGP router
ROUTER BGP mode
bgp router-id ip-address
ip-address- IP address in dotted decimal format.
NOTE: Do not specify an IP address which is used by another device as a router ID.
Peering sessions are reset when you change the router ID of a BGP router. Upon changing the router ID, the system automatically
restarts the BGP instance for the conguration to take eect.
Example of changing BGP router ID
DellEMC# configure terminal
DellEMC(conf)# router bgp 400
DellEMC(conf-router_bgp)# bgp router-id 1.1.1.1
Following is the sample output of show ip bgp ipv4 multicast summary command.
DellEMC# show ip bgp summary
BGP router identifier 1.1.1.1, local AS number 400
BGP local RIB : Routes to be Added 0, Replaced 0, Withdrawn 0
1 neighbor(s) using 8192 bytes of memory
Neighbor AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/Pfx
20.20.20.1 200 0 0 0 0 0 00:00:00 0
DellEMC#
Conguring AS4 Number Representations
Enable one type of AS number representation: ASPLAIN, ASDOT+, or ASDOT.
Term
Description
ASPLAIN
Default method for AS number representation. With the ASPLAIN notation, a 32–bit binary AS number is
translated into a decimal value.
ASDOT+ A representation splits the full binary 4-byte AS number into two words of 16 bits separated by a decimal point (.):
<high-order 16 bit value>.<low-order 16 bit value>.
ASDOT A representation combines the ASPLAIN and ASDOT+ representations. AS numbers less than 65536 appear in
integer format (asplain); AS numbers equal to or greater than 65536 appear using the decimal method (asdot+).
For example, the AS number 65526 appears as 65526 and the AS number 65546 appears as 1.10.
NOTE: The ASDOT and ASDOT+ representations are supported only with the 4-Byte AS numbers feature. If you do not
implement 4-Byte AS numbers, only ASPLAIN representation is supported.
Only one form of AS number representation is supported at a time. You cannot combine the types of representations within an AS.
To congure AS4 number representations, use the following commands.
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Border Gateway Protocol (BGP)