Alcatel-Lucent 7750 SR-OS, Configuration Manual

Page: 110 / 674

Router Global Commands
Page 110 7750 SR OS Router Configuration Guide
Router Global Commands
router
Syntax router router-name
Context config
Description This command enables the context to configure router parameters, and interfaces, route policies, and
protocols.
Parameters router-name — Specify the router-name.
Values router-name: Base, management
Default Base
aggregate
Syntax aggregate ip-prefix/ip-prefix-length [ summary-only ] [ as-set ] [ aggregator as-number: ip-
address ] [ community comm-id ] [ black-hole | indirect ip-address ]
no aggregate ip-prefix/ip-prefix-length
Context config>router
Description This command creates an aggregate route.
Use this command to automatically install an aggregate in the routing table when there are one or
more component routes. A component route is any route used for forwarding that is a more-specific
match of the aggregate.
The use of aggregate routes can reduce the number of routes that need to be advertised to neighbor
routers, leading to smaller routing table sizes.
Overlapping aggregate routes may be configured; in this case a route becomes a component of only
the one aggregate route with the longest prefix match. For example if one aggregate is configured as
10.0.0.0/16 and another as 10.0.0.0/24, then route 10.0.128/17 would be aggregated into 10.0.0.0/16,
and route 10.0.0.128/25 would be aggregated into 10.0.0.0/24. If multiple entries are made with the
same prefix and the same mask the previous entry is overwritten.
A standard 4-byte BGP community may be associated with an aggregate route in order to facilitate
route policy matching.
By default aggregate routes are not installed in the forwarding table, however there are configuration
options that allow an aggregate route to be installed with a black-hole next hop or with an indirect IP
address as next hop.
The no form of the command removes the aggregate.
Default No aggregate routes are defined.