Reference Guide

Border Gateway Protocol IPv4 (BGPv4) | 319
Command Modes
ROUTER BGP ADDRESS FAMILY
ROUTER BGP ADDRESS FAMILY IPv6
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 will still appear 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.
Command
History
.
bgp always-compare-med
c e s
Enables 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, enter no bgp always-compare-med.
Defaults
Disabled (that is, the software only compares MEDs from neighbors within the same AS).
Command Modes
ROUTER BGP
Usage
Information
Any update without a MED attribute is the least preferred route
If you enable this command, use the clear ip bgp ipv4 unicast soft * command to recompute the best
path.
Command
History
.
Version 7.8.1.0 Introduced support on S-Series
Version 7.7.1.0 Introduced support on C-Series
Version 8.2.1.0 Introduced command
Version 7.7.1.0 Introduced support on C-Series