D-Link DXS-3600-EM-8T CLI Guide - Page 76

bgp always-compare-med

Page 76 highlights

DXS-3600 Series 10GbE Layer 2/3 Switch CLI Reference Guide Command Default Level Usage Guideline Level: 8. (EI Mode Only Command) This command is used to enable the checking of next hop of the BGP aggregated routes. Only the routes with the same next hop attribute can be aggregated if the BGP aggregate next hop check is enabled. Using the no form of this command is to disable the bgp aggregate-next-hop-check. You can verify your settings by entering the show ip bgp parameters command. Example This example shows how to configure the BGP aggregate-next-hop-checking state. DXS-3600-32S#configure terminal DXS-3600-32S(config)#router bgp 65534 DXS-3600-32S(config-router)#bgp aggregate-next-hop-check DXS-3600-32S(config-router)# 7-6 bgp always-compare-med This command is used to enable the comparison of the Multi Exit Discriminator (MED) for paths from neighbors in different autonomous systems. Use the no form of this command to disallow the comparison. bgp always-compare-med no bgp always-compare-med Parameters Default Command Mode Command Default Level Usage Guideline None. The default option is disabled. Router Configuration. Level: 8. (EI Mode Only Command) The MED, as stated in RFC 1771, is an optional non-transitive attribute that is a four octet non-negative integer. The value of this attribute may be used by the BGP best path selection process to discriminate among multiple exit points to a neighboring autonomous system. The MED is one of the parameters that are considered when selecting the best path among many alternative paths. The path with a lower MED is preferred over a path with a higher MED. During the best-path selection process, MED comparison is done only among paths from the same autonomous system. The bgp always-comparemed command is used to change this behavior by enforcing MED comparison between all paths, regardless of the autonomous system from which the paths are received. The bgp deterministic-med command can be configured to enforce deterministic comparison of the MED value between all paths received from within the same autonomous system. You can verify your settings by entering show ip bgp parameters command. Example This example shows how to configure the switch to compare the MED from alternative paths, regardless of the autonomous system from which the paths are received. DXS-3600-32S#configure terminal DXS-3600-32S(config)#router bgp 65534 DXS-3600-32S(config-router)#bgp always-compare-med DXS-3600-32S(config-router)# 68

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DXS-3600 Series 10GbE Layer 2/3 Switch CLI Reference Guide
68
7-6
bgp always-compare-med
This command is used to enable the comparison of the Multi Exit Discriminator (MED) for paths from neighbors in
different autonomous systems. Use the no form of this command to disallow the comparison.
bgp always-compare-med
no bgp always-compare-med
Command Default Level
Level: 8. (
EI Mode Only Command
)
Usage Guideline
This command is used to enable the checking of next hop of the BGP aggregated
routes. Only the routes with the same next hop attribute can be aggregated if the
BGP aggregate next hop check is enabled. Using the no form of this command is to
disable the bgp aggregate-next-hop-check.
You can verify your settings by entering the
show ip bgp parameters
command.
Example
This example shows how to configure the BGP aggregate-next-hop-checking state.
DXS-3600-32S#configure terminal
DXS-3600-32S(config)#router bgp 65534
DXS-3600-32S(config-router)#bgp aggregate-next-hop-check
DXS-3600-32S(config-router)#
Parameters
None.
Default
The default option is disabled.
Command Mode
Router Configuration.
Command Default Level
Level: 8. (
EI Mode Only Command
)
Usage Guideline
The MED, as stated in RFC 1771, is an optional non-transitive attribute that is a four
octet non-negative integer. The value of this attribute may be used by the BGP best
path selection process to discriminate among multiple exit points to a neighboring
autonomous system.
The MED is one of the parameters that are considered when selecting the best path
among many alternative paths. The path with a lower MED is preferred over a path
with a higher MED. During the best-path selection process, MED comparison is done
only among paths from the same autonomous system. The
bgp always-compare-
med
command is used to change this behavior by enforcing MED comparison
between all paths, regardless of the autonomous system from which the paths are
received.
The
bgp deterministic-med
command can be configured to enforce deterministic
comparison of the MED value between all paths received from within the same
autonomous system.
You can verify your settings by entering
show ip bgp parameters
command.
Example
This example shows how to configure the switch to compare the MED from
alternative paths, regardless of the autonomous system from which the paths are
received.
DXS-3600-32S#configure terminal
DXS-3600-32S(config)#router bgp 65534
DXS-3600-32S(config-router)#bgp always-compare-med
DXS-3600-32S(config-router)#