3Com Router 3000 Ethernet FamilyConfiguration Guide Chapter 6 BGP Configuration3Com Corporation6-16Table 6-29 Configure BGP route aggregationOperation CommandConfigure the subnet routes automaticsummary function summaryCancel the subnet routes automaticsummary function undo summaryConfigure the local route aggregationfunctionaggregate address mask [ as-set ][ detail-suppressed ][ suppress-policy route-policy-name ][ origin-policy route-policy-name ][ attribute-policy route-policy-name ]Cancel the local route aggregationfunctionundo aggregate address mask[ as-set ] [ detail-suppressed ][ suppress-policy route-policy-name ][ origin-policy route-policy-name ]attribute-policyroute-policy-name ]policy-name ][ attribute-policy policy-name ]By default, BGP does not aggregate subnet routes and local routes.6.2.12 Configuring the BGP PreferenceEach routing protocol has its own preference, by which the routing policy will select theoptimal one from the routes of different protocols. The greater the preference value is,the lower the preference becomes. BGP has three kinds of routes: routes learned fromexternal peers, routes learned from internal peers, and the local routes. You canmanually set BGP preferences for these three kinds of routes respectively.Different sub-address families can be set with different BGP preferences. Both unicastaddress family and multicast address family are supported currently.Perform the following configuration in BGP view or BGP multicast address family view.Table 6-30 Configure the BGP preferenceOperation CommandConfigure the BGP preference preference value1 value2 value3Restore the default preference values undo preferenceWhere value1 is for routes learned from EBGP peers, value2 is for routes learned fromIBGP peers, and value3 is for local routes. They can be in the range 1 to 256.By default, value1, value2, value3 are 256, 256, and 130 respectively.
