Huawei Quidway NetEngine80E Configuration Manual page 915

HUAWEI NetEngine80E/40E Router
Configuration Guide - IP Routing
Abbr
eviate
d
Alias
M
T
C
C
R
A
Selection of the Routes for Load Balancing
After BGP load balancing is configured, the BGP routes that meet the following conditions are
used as equal-cost routes for load balancing:
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Issue 02 (2014-09-30)
Matching Route Selection Rules
Item
Multi Exit The route with the
Discriminator smallest MED value is
(MED) preferred.
The default value is 0.
Peer type EBGP > IBGP
IGP cost The route with the
smallest IGP cost is
preferred.
Cluster_List The route with the
shortest Cluster_List
length is preferred.
Router ID The route with the
smallest router ID is
preferred.
Peer IP The route learned from
address the peer with the smallest
IP address is preferred.
The routes have the same PrefVal value.
The routes have the same Local_Pref value.
All the routes are summarized or non-summarized routes.
The routes have the same AIGP value.
The routes have the same AS_Path length.
The routes have the same origin type (IGP, EGP, or incomplete).
The routes have the same MED value.
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8 BGP Configuration
Remarks
If the bestroute med-none-as-
maximum command is configured,
BGP considers the largest MED value
(4294967295) as the MED of the route
that does not carry an MED.
For details about MED usage, see
MED.
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If the bestroute igp-metric-ignore
command is configured, BGP does not
compare the IGP cost.
By default, Cluster_List takes
precedence over Originator_ID during
BGP route selection. To enable
Originator_ID to take precedence over
Cluster_List during BGP route
selection, run the bestroute routerid-
prior-clusterlist command.
If routes carry the Originator_ID, the
originator ID is substituted for the
router ID during route selection. The
route with the smallest Originator_ID
is preferred.
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