ECS4660-28F_Management Guide-R03

C HAPTER 51 | IP Routing Commands
Border Gateway Protocol (BGPv4)
– 1834 –
EXAMPLE
The regular expression in this example uses symbols which instruct the
filter to match the character or null string at the beginning and end of an
input string.
Console(config-router)#ip as-path access-list RD deny ^100$
Console(config-router)#
RELATED COMMANDS
neighbor filter-list (1867)
match as-path (1902)
ip community-list This command configures a community access list. Use the no form with
only the access list name to disable its use, or with all parameters to
remove a community attribute from the access list.
SYNTAX
[no] ip community-list
{1-99 | standard community-list-name {deny | permit}
[AA:NN] [internet] [local-as] [no-advertise] [no-export]} |
{100-500 | expanded community-list-name {deny | permit}
regular-expression}
1-99 – Standard community list number that identifies one or more
groups of communities.
standard community-list-name – Name of standard access list.
A maximum of 16 communities can be configured in a standard
community list (Maximum length: 32 characters, no spaces or other
special characters)
deny – Denies access to messages with matching community
attribute.
permit – Permits access for messages with matching community
attribute.
AA:NN – Standard community-number to deny or permit. The
4-byte community number is composed of a 2-byte autonomous
system number and a 2-byte network number, separated by one
colon. Each 2-byte number can range from 0 to 65535. One or more
communities can be entered, separated by a space. Up to 16
community numbers are supported.
internet – Specifies the entire Internet. Routes with this
community attribute are advertised to all internal and external
peers.
local-as – Specifies the local autonomous system. Routes with this
community attribute are advertised only to peers that are part of
the local autonomous system or to peers within a sub-autonomous
system of a confederation. These routes are not advertised to
external peers or to other sub-autonomous systems within a
confederation.