Operation Manual – Routing ProtocolH3C S7500 Series Ethernet Switches Chapter 6 BGP Configuration6-10by importing IGP routing information to BGP routing table. Once IGP routinginformation is imported to BGP routing table, it is advertised to BGP peers. You canfilter IGP routing information by routing protocols before the IGP routing information isimported to BGP routing table.Follow these steps to import routes:To do... Use the command... RemarksEnter system view system-view —Enter BGP view bgp as-number —Import and advertiserouting informationgenerated by otherprotocols.import-route protocol[ process-id ] [ medmed-value | route-policyroute-policy-name ]*RequiredBy default, BGP neitherimport nor advertise therouting informationgenerated by otherprotocols.Advertise networksegment routes to BGProuting tablenetwork network-address[ mask ] route-policyroute-policy-name ]OptionalBy default, BGP does notadvertise any networksegment routes.Caution:z If a route is imported to the BGP routing table through the import-route command,its Origin attribute is Incomplete.z The network segment route to be advertised must be in the local IP routing table.You can use routing policy to control route advertising with more flexibility.z The Origin attribute of the network segment routes advertised to BGP routing tablethrough the network command is IGP.6.4.3 Configuring BGP Route AggregationIn a medium-/large-sized BGP network, you can reduce the number of the routes tobe advertised to BGP peers through route aggregation to save the space of BGP peerrouting tables. BGP supports two route aggregation modes: automatic aggregationmode and manual aggregation mode.z Automatic aggregation mode, where IGP sub-network routes imported by BGPare aggregated. In this mode, only the aggregated routes are advertised. Theimported IGP sub-network routes are not advertised. Note that the default routesand the routes imported by using the network command cannot be automaticallyaggregated.
