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aggregate-address
Summarize a range of prefixes to minimize the number of entries in the routing table.
Syntax
aggregate-address ipv6-address prefix-mength [advertise-map map-name] [as-
set] [attribute-map map-name] [summary-only] [suppress-map map-name]
Parameters
ipv6-address
prefix-length
Enter the IPv6 address in the x:x:x:x::x format then the prefix length in the / x
format. The range is from /0 to /128.
NOTE: The :: notation specifies successive hexadecimal fields of zeros.
advertise-map
map-name
(OPTIONAL) Enter the keywords advertise-map then the name of a configured
route map to set filters for advertising an aggregate route.
as-set (OPTIONAL) Enter the keywords as-set to generate path attribute information
and include it in the aggregate. AS_SET includes AS_PATH and community
information from the routes included in the aggregated route.
attribute-map
map-name
(OPTIONAL) Enter the keywords attribute-map then the name of a configured
route map to modify attributes of the aggregate, excluding AS_PATH and
NEXT_HOP attributes.
summary-only (OPTIONAL) Enter the keywords summary-only to advertise only the aggregate
address. Specific routes are not advertised.
suppress-map
map-name
(OPTIONAL) Enter the keywords suppress-map then the name of a configured
route map to identify which more-specific routes in the aggregate are suppressed.
Defaults Not configured.
Command Modes
● ROUTER BGP ADDRESS FAMILY
● ROUTER BGP ADDRESS FAMILY IPv6
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
At least one of the routes included in the aggregate address must be in the BGP routing table for the
configured aggregate to become active.
Do not add the as-set parameter to the aggregate if routes within the aggregate are constantly
changing as the aggregate will flap to keep track of the changes in the AS_PATH.
In route maps used in the suppress-map parameter, routes meeting the deny clause are not suppress;
in other words, they are allowed. The opposite is true: routes meeting the permit clause are suppressed.
If the route is injected using the network command, that route still appears in the routing table if you
configure the summary-only parameter in the aggregate-address command.
The summary-only parameter suppresses all advertisements. If you want to suppress advertisements to
only specific neighbors, use the neighbor distribute-list command.
In the show ip bgp ipv6 unicast command, aggregates contain an ‘a’ in the first column and
routes suppressed by the aggregate contain an ‘s’ in the first column.
bgp always-compare-med
Allows you to enable comparison of the MULTI_EXIT_DISC (MED) attributes in the paths from different external ASs.
Syntax
bgp always-compare-med
To disable comparison of MED, use the no bgp always-compare-med command.
604 IPv6 Border Gateway Protocol (IPv6 BGP)