D-Link DXS-3600-16S, Руководство пользователя

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DXS-3600 Series 10GbE Layer 2/3 Switch CLI Reference Guide
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7-19 bgp deterministic-med
This command is used to include the Multi Exit Discriminator (MED) value between all paths received from within the
same autonomous system in the process of the best route selection. Use the no command to prevent BGP from
considering the MED attribute in comparing paths.
bgp deterministic-med
no bgp deterministic-med
7-20 bgp enforce-first-as
This command is used to enforce the first AS for eBGP routes. To disable this feature, use the no form of this
command.
bgp enforce-first-as
no bgp enforce-first-as
Parameters None.
Default By default, this option is disabled.
Command Mode Router Configuration Mode.
Command Default Level Level: 8. ( EI Mode Only Command )
Usage Guideline This command is used to enable the comparison of the Multi Exit Discriminator
(MED) for paths from neighbors in different autonomous systems. After this
command is configured, all paths for the same prefix, that are received from different
neighbors, which are in the same autonomous system, will be grouped together and
sorted by the ascending MED value (received-only paths are ignored and not
grouped or sorted).
The best path selection algorithm will then pick the best paths using the existing
rules. The comparison is made on a peer neighbor autonomous system basis and
then the global basis. The grouping and sorting of paths occurs immediately after
this command was entered. For the correct results, all routers in the local
autonomous system must have this command enabled (or disabled).
This command can also be configured to enforce a deterministic comparison of the
MED values between all paths received from within the same autonomous system.
You can verify your settings by entering the show ip bgp parameters command.
Example This example shows how to configure to switches to enable the compare MED value
for autonomous system 65534,
DXS-3600-32S#configure terminal
DXS-3600-32S(config)#router bgp 65534
DXS-3600-32S(config-router)#bgp deterministic-med
DXS-3600-32S(config-router)#
Parameters None.
Default By default, this option is disabled.
Command Mode Router Configuration Mode.
Command Default Level Level: 8. ( EI Mode Only Command )
Usage Guideline This command specifies that any updates received from an external neighbor, that
do not have neighbor’s configured in an Autonomous System at the beginning of the
AS-PATH attribute in the received update, must be denied. Enabling this feature
adds to the security of the BGP network by not allowing traffic from unauthorized
systems.
You can verify your settings by entering the show ip bgp parameters command.