Foundry Networks FESX User Manual

Foundry Configuration Guide for the FESX, FSX, and FWSX
21 - 46 © Foundry Networks, Inc. December 2005
The local-as keyword checks for routes with the well-known community “LOCAL_AS”. This community applies
only to confederations. The Layer 3 Switch advertises the route only within the sub-AS. For information about
confederations, see “Configuring Confederations” on page 21-34.
The no-advertise keyword filters for routes with the well-known community “NO_ADVERTISE”. A route in this
community should not be advertised to any BGP4 neighbors.
The no-export keyword filters for routes with the well-known community “NO_EXPORT”. A route in this
community should not be advertised to any BGP4 neighbors outside the local AS. If the router is a member of a
confederation, the Layer 3 Switch advertises the route only within the confederation. For information about
confederations, see “Configuring Confederations” on page 21-34.
Defining a Community ACL
To configure community ACL 1, enter a command such as the following:
FESX424 Router(config)# ip community-list 1 permit 123:2
This command configures a community ACL that permits routes that contain community 123:2.
NOTE: See “Matching Based on Community ACL” on page 21-51 for information about how to use a community
list as a match condition in a route map.
Syntax: ip community-list standard <string> [seq <seq-value>] deny | permit <community-num>
Syntax: ip community-list extended <string> [seq <seq-value>] deny | permit
<community-num> | <regular-expression>
The <string> parameter specifies the ACL name. (If you enter a number, the CLI interprets the number as a text
string.)
The standard or extended parameter specifies whether you are configuring a standard community ACL or an
extended one. A standard community ACL does not support regular expressions whereas an extended one does.
This is the only difference between standard and extended IP community lists.
The seq <seq-value> parameter is optional and specifies the community list’s sequence number. You can
configure up to 199 entries in a community list. If you do not specify a sequence number, the software numbers
them in increments of 5, beginning with number 5. The software interprets the entries in a community list in
numerical order, beginning with the lowest sequence number.
The deny | permit parameter specifies the action the software takes if a route’s community list matches a match
statement in this ACL. To configure the community-list match statements in a route map, use the match
community command. See “Matching Based on Community ACL” on page 21-51.
The <community-num> parameter specifies the community type or community number. This parameter can have
the following values:
•<num>:<num> – A specific community number
• internet – The Internet community
• no-export – The community of sub-ASs within a confederation. Routes with this community can be exported
to other sub-ASs within the same confederation but cannot be exported outside the confederation to other
ASs or otherwise sent to EBGP neighbors.
• local-as – The local sub-AS within the confederation. Routes with this community can be advertised only
within the local subAS.
• no-advertise – Routes with this community cannot be advertised to any other BGP4 routers at all.
The <regular-expression> parameter specifies a regular expression for matching on community names. For
information about regular expression syntax, see “Using Regular Expressions” on page 21-42. You can specify a
regular expression only in an extended community ACL.

Foundry Networks FESX Specifications

General

Brand	Foundry Networks
Model	FESX
Category	Switch
Language	English