Technical data

Gateway Routing Daemon (GATED) Configuration Reference
A.18 Control Statements
• aspath_term | aspath_term
Matches the AS term on the left, or the AS term on the right.
A.18.3 The Import Statement
Importation of routes from routing protocols and installation of the routes in
GATED’S routing database is controlled by import statements. The format of an
import statement varies depending on the source protocol.
A.18.3.1 Specifying Preferences
You can specify one of the following keywords to control how routes compete with
other protocols:
restrict
preference preference
In these statements:
• restrict specifies that the routes are not desired in the routing table. In
some cases this means that the routes are not installed in the routing table.
In others it means that they are installed with a negative preference; this
prevents them from becoming active so they will not be installed in the
forwarding table, or exported to other protocols.
•
preference specifies the preference value used when comparing this route
to other routes from other protocols. The route with the lowest preference
available at any given route becomes the active route, is installed in the
forwarding table, and is eligible to be exported to other protocols. The default
preferences are configured by the individual protocols.
A.18.3.2 Route Filters
All the formats allow route filters described in this section. When no route
filtering is specified (that is, when restrict is specified on the first line of a
statement), all routes from the specified source will match that statement. If any
filters are specified, only routes that match the specified filters will be imported.
That is, if any filters are specified, a statement like all restrict ; is assumed at
the end of the list.
network [ exact | refines | between number and number]
network mask mask [exact | refines | between number and number ]
network masklen number [ exact | refines | between number and number ]
default
host host
A.18.3.3 Importing Routes from BGP and EGP
Use the following syntax to define importing routes from BGP and EGP:
import proto bgp | egp autonomoussystem autonomous_system
[ aspath-opt ] restrict ;
import proto bgp | egp autonomoussystem autonomous_system
[ aspath-opt ] [ preference preference ]{
route_filter [ restrict | ( preference preference )];
};
Gateway Routing Daemon (GATED) Configuration Reference A–35