Administrator Guide

Defaults Not configured.
Command Modes CONFIGURATION-ROUTER-BGPV6-ADDRESS FAMILY
Command
History
Version Description
9.9(0.0) Introduced on the C9010.
9.2(1.0) Introduced on the Z9500.
8.2.1.0 Introduced on the E-Series ExaScale.
7.4.1.0 Introduced
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 via the network command, that route still appears in the routing table if the
summary-only parameter is configured 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 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.
C9000 Series
Syntax
bgp always-compare-med
To disable comparison of MED, use the no bgp always-compare-med command.
Defaults Disabled (that is, the software only compares MEDs from neighbors within the same AS).
Command Modes ROUTER BGP
Command
History
Version Description
9.9(0.0) Introduced on the C9010.
9.2(1.0) Introduced on the Z9500.
8.2.1.0 Introduced on the E-Series ExaScale.
7.4.1.0 Introduced
Usage
Information
Any update without a MED attribute is the least preferred route.
If you enable this command, use the clear ip bgp * command to recompute the best path.
440 Border Gateway Protocol