Zte ZXR10 GER, Руководство пользователя

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ZXR10 GER (V2.6.03) General Excellent Router User Manual Volume-I
242 Confidential and Proprietary Information of ZTE CORPORATION
ZXR10_R4(config-route-map)#set local-preference 200
ZXR10_R4(config)#route-map setlocalin permit 20
ZXR10_R4(config-route-map)#set local-preference 150
MED Attribute
The “metric” attribute is also called the MED
(Multi_Exit_Discrimination) attribute, which is used for route
interaction and decision among ASs.
By default, a router only compares the metric value of BGP
neighbors from the same AS.
Refer to below procedure for MED attribute configuration on ZTE
ZXR10 GER.
„
Refer Router Command Line Interface has been accessed.
„
BGP is running on a network.
1. If neighbors from different ASs are to be compared, use bgp
always-compare-med command in BGP route mode as
shown in Table 294.
T
A B L E
2 9 4 B
G P
A
L W A Y S
M
E D
A
T T R I B U T E
C
O M M A N D
Command
Format
Command
Mode
Command Function
bgp always-
compare-med
Route
This configures the local
precedence value of routes
advertised by BGP
Result: This configures the local precedence value of routes
advertised by BGP.
The default metric value is 0. Smaller is the metric value, the
higher the priority. The metric value cannot be transplanted
to a third AS, that is, if a router receives an update
configured with metric value and also the update needs to be
transferred to a third AS, the router will transfer the update
with the default metric value.
As shown in Figure 100, R1 receives updates of 180.10.0.0 from
R2, R3 and R4 simultaneously. By default, only the metric values
of neighbors R3 and R4 in the same AS are compared. The
metric value of R3 is less than that of R4, so for the updates of
180.10.0.0. R1 will only accept the update of R3.
Introduction
Purpose
Prerequisites
Steps