Users Guide

The following example shows verifying the BGP configuration.
R2#show running-config bgp
!
router bgp 65123
bgp router-id 192.168.10.2
network 10.10.21.0/24
network 10.10.32.0/24
network 100.10.92.0/24
network 192.168.10.0/24
bgp four-octet-as-support
neighbor 10.10.21.1 remote-as 65123
neighbor 10.10.21.1 filter-list ISP1in
neighbor 10.10.21.1 no shutdown
neighbor 10.10.32.3 remote-as 65123
neighbor 10.10.32.3 no shutdown
neighbor 100.10.92.9 remote-as 65192
neighbor 100.10.92.9 no shutdown
neighbor 192.168.10.1 remote-as 65123
neighbor 192.168.10.1 update-source Loopback 0
neighbor 192.168.10.1 no shutdown
neighbor 192.168.12.2 remote-as 65123
neighbor 192.168.12.2 update-source Loopback 0
neighbor 192.168.12.2 no shutdown
R2#
Configuring 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 that 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 that 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 configure AS4 number representations, use the following commands.
• Enable ASPLAIN AS Number representation.
CONFIG-ROUTER-BGP mode
bgp asnotation asplain
NOTE: ASPLAIN is the default method used to represent AS numbers and does not appear in the
configuration display.
Border Gateway Protocol IPv4 (BGPv4) 214