User's Manual
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If each route has the same value, preferably select the route with the maximum local
precedence.
If each route has the same local precedence, select preferably the route generated by local
router. For example, route may be generated by local router through the using of command
“network, aggregate” or by redistributing IGP route.
If the local precedences are the same, or if there is no route generated by local router, then
select preferably the route with the shortest AS path.
If the AS path lengths are the same, then select preferably the route with the lowest attribute
value of “origin” (IGP<EGP<IMCOMPLETE)
If the attribute values of “Origin” are the same, then select preferable route with the lowest
MED value. Unless “bgp always-compare-med” is activated, this comparable can only be
carried out between the routes from the same neighbour AS.
If each route has the same MED, select preferable external path (EBGP) rather than internal
path (IBGP). All paths inside the autonomous system confederation are considered to be
internal paths, but select preferably EBGP confederation not IBGP confederation.
If each route has the same connection attribute, select preferable route with a smaller router-
id.
61.2 BGP Configuration Task List
61.2.1 Basic configuration task list of BGP
The configuration tasks of BGP can be divided into basic tasks and advanced tasks. The first two entries of
basic tasks are necessary to configure BGP, other entries in basic tasks and all advanced tasks are optional.
The basic configuration tasks of BGP include:
Activate the route selection of BGP.
Configure BGP neighbor.
Configure BGP soft reconfiguration
Reset BGP connection.
Configure the synchronization between BGP and IGPs
Configure BGP route value
Configure BGP route filter based on the neighbour
Configure BGP route filtration based on the interface
Disable the nexthop treatment of BGP update
61.2.2 Advanced BGP configuration tasks list
Advanced, optional BGP configuration tasks are listed as the following:
Use route-map to filter and modify route update
Configure aggregate address
Configure BGP community attribute
Configure autonomous system confederation
Configure route reflector
Shut down peer entity
Configure multihop external peer body
Configure the management distance of BGP routes
Adjust BGP timer.