Configuring The Bgp Preference - Huawei Quidway NetEngine80E Configuration Manual

HUAWEI NetEngine80E/40E Router
Configuration Guide - IP Routing
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Pre-configuration Tasks
Before configuring BGP route attributes, complete the following tasks:
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Data Preparation
To configure BGP route attributes, you need the following data.
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8.4.2 Configuring the BGP Preference

Setting the BGP preference can affect route selection between BGP routes and other routing
protocols' routes.
Context
Multiple dynamic routing protocols can be run on a device at the same time. In this case, there
is a problem of route sharing and selecting among routing protocols. To address this problem,
the system sets a default preference for each routing protocol. If different protocols have routes
to the same destination, the protocol with the highest preference is selected to forward IP packets.
Perform the following steps on a device running BGP.
Procedure
Step 1 Run:
Issue 02 (2014-09-30)
The MED attribute is used to determine the optimal route for traffic that enters an AS. The
route with the smallest MED value is selected as the optimal route if the other attributes of
the routes are the same.
Next_Hop
BGP route selection can be flexibly controlled by changing Next_Hop attributes for routes.
AS_Path
The AS_Path attribute is used to prevent rooting loops and control route selection.
Accumulated Interior Gateway Protocol Metric (AIGP)
The AIGP attribute is used to select the optimal route in an AIGP administrative domain.
Configuring IP addresses for interfaces to ensure IP connectivity between neighboring
nodes
Configuring Basic BGP Functions
Data
AS number
BGP preference value
Local_Pref value
MED value
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