Technical Tip: Configure 4 bytes ASN in BGP

[mprabakhar]

Description

This article describes how to add Four-octet ASN in BGP config.

https://docs.fortinet.com/document/fortigate/6.0.0/handbook/242461/dynamic-routing-terminology
These new 4-byte AS numbers (range from 65536 to 4294967295) can be written in three ways:

External.

APNIC – ASN Convertor - https://submit.apnic.net/cgi-bin/convert-asn.pl
Adding the dotted notation will fail as seen below.

FGT # config router bgp
FGT (bgp) # set as
as            <----- Enter an integer value from <0> to <4294967295>.
FGT (bgp) # set as 65001.65001
invalid integer value: .65001
value parse error before '65001.65001'
Command fail. Return code -1

Solution

To add 4 bytes AS numbers, the dotted notation has to be converted to decimal notation to be added to the config.

+  Can be converted in the APNIC converter tool ,  https://submit.apnic.net/cgi-bin/convert-asn.pl  
+ '65001.65001' is Converted to ASN: 4259970537.

FGT # config router bgp
FGT (bgp) # set as 4259970537
FGT (bgp) # show
# config router bgp
(bgp) # set as 4259970537