Users Guide

BGP Extended Communities (RFC 4360)
BGP Extended Communities, as defined in RFC 4360, is an optional transitive BGP attribute.
BGP Extended Communities provides two major advantages over Standard Communities:
● The range is extended from 4-octet (AA:NN) to 8-octet (Type:Value) to provide enough number communities.
● Communities are structured using a new “Type” field (1 or 2-octets), allowing you to provide granular control/filter routing
information based on the type of extended communities.
set extcommunity rt
To set Route Origin community attributes in Route Map, use this feature.
Syntax
set extcommunity rt {as4 ASN4:NN [non-trans] | ASN:NNNN [non-trans] |
IPADDR:NN [non-trans]} [additive]
To delete the Route Origin community, use the no set extcommunity command.
Parameters
as4 ASN4:NN Enter the keyword as4 then the 4-octet AS specific extended community number
in the format ASN4:NN (4-byte AS number:2-byte community value).
ASN:NNNN Enter the 2-octet AS specific extended community number in the format
ASN:NNNN (2-byte AS number:4-byte community value).
IPADDR:NN Enter the IP address specific extended community in the format IPADDR:NN (4-
byte IPv4 Unicast Address:2-byte community value).
additive (OPTIONAL) Enter the keyword additive to add to the existing extended
community.
non-trans (OPTIONAL) Enter the keywords non-trans to indicate a non-transitive BGP
extended community.
Defaults none
Command Modes ROUTE MAP (config-route-map)
Command
History
This guide is platform-specific. For command information about other platforms, see the relevant Dell
Networking OS Command Line Reference Guide.
Version Description
9.8(2.0) Introduced on the S3100 series.
9.8(0.0P5) Introduced on the S4048-ON.
9.8(0.0P2) Introduced on the S3048-ON.
9.2(1.0) Introduced on the Z9500.
8.3.19.0 Introduced on the S4820T
8.3.11.1 Introduced on the Z-9000.
8.3.7.0 Introduced on the S4810.
7.8.1.0 Introduced on the S-Series.
7.7.1.0 Introduced on the C-Series.
7.6.1.0 Introduced on the E-Series.
Usage
Information
If the set community rt and soo are in the same route-map entry, the behavior defines as:
● If the rt option comes before soo, with or without the additive option, soo overrides the
communities rt sets.
416 Border Gateway Protocol