756 BigIron RX Series Configuration Guide53-1001986-01Changing the default local preference26BigIron RX(config-bgp)# default-information-originateSyntax: [no] default-information-originateChanging the default local preferenceWhen the router uses the BGP4 algorithm to select a route to send to the IP route table, one of theparameters the algorithm uses is the local preference. Local preference is an attribute thatindicates a degree of preference for a route relative to other routes. BGP4 neighbors can send thelocal preference value as an attribute of a route in an UPDATE message.Local preference applies only to routes within the local AS. BGP4 routers can exchange localpreference information with neighbors who also are in the local AS, but BGP4 routers do notexchange local preference information with neighbors in remote ASs.The default local preference is 100. For routes learned from EBGP neighbors, the default localpreference is assigned to learned routes. For routes learned from IBGP neighbors, the localpreference value is not changed for the route.When the BGP4 algorithm compares routes on the basis of local preferences, the route with thehigher local preference is chosen.NOTETo set the local preference for individual routes, use route maps. Refer to “Defining route maps” onpage 791. Refer to “How BGP4 selects a path for a route” on page 732 for information about theBGP4 algorithm.To change the default local preference to 200, enter the following command.BigIron RX(config-bgp)# default-local-preference 200Syntax: default-local-preference The parameter indicates the preference and can be a value from 0 – 4294967295.Changing the default metric used for redistributionThe BigIron RX can redistribute directly connected routes, static IP routes, RIP routes, ISIS routes,and OSPF routes into BGP4. By default, BGP uses zero (0) for direct connected routes and themetric (MED) value of IGP routes in the IP route table. The MED is a global parameter that specifiesthe cost that will be applied to all routes, if assigned, when they are redistributed into BGP4. Whenroutes are selected, lower metric values are preferred over higher metric values. The default, theBGP4 MED value is not assigned.NOTERIP, ISIS, and OSPF also have default metric parameters. The parameters are set independently foreach protocol and have different ranges.To change the default metric to 40, enter the following command.BigIron RX(config-bgp)# default-metric 40Syntax: default-metric The indicates the metric and can be a value from 0 – 4294967295.
