Juniper JUNOSE 11.2.X BGP AND MPLS, Руководство по настройке

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Use to modify an AS path for BGP routes by prepending one or more AS numbers or a
list of AS numbers to the path list.
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The only global BGP metric available to influence the best-path selection is the AS-path
length. By varying the length of the AS path, a BGP speaker can influence the best-path
selection by a peer farther away.
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Example
host1(config)# route-map nyc1 permit 10
host1(config-route-map)# set as-path prepend list list10
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Use the no version to delete the set clause from a route map.
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See set as-path prepend.
set comm-list delete
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Use to remove communities specified by the community list from the community
attribute of routes matching the route map.
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You can use this command to delete communities only if the community list was
created with a single community per list entry as shown in the following sample
configuration for router Test:
host1(config)# ip community-list 1 permit 231:10
host1(config)# ip community-list 1 permit 231:20
host1(config)# router bgp 45
host1(config-router)# neighbor 10.6.2.5 remote-as 5
host1(config-router)# neighbor 10.6.2.5 route-map indelete in
host1(config-router)# route-map indelete permit 10
host1(config-route-map)# set comm-list 1 delete
Router Test receives the same route from 10.6.2.5 and applies the indelete route map.
BGP compares each list entry with the community attribute. A match is found for the
list entry 231:10, and this community is deleted from the community attribute. Similarly,
a match is found for the list entry of 231:20, and this community is deleted from the
community attribute.
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Use the no version to delete the set clause from a route map.
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See set comm-list delete.
set community
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Use to set the community attribute in BGP updates.
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You can specify a community list number in the range 1–4294967295, or in the new
community format of AA:NN, or one of the following well-known communities:
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local-as —Prevents advertisement outside the local AS
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no-advertise —Prevents advertisement to any peer
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no-export —Prevents advertisement beyond the BGP confederation boundary
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Alternatively, you can use the list keyword to specify the name of a community list
that you previously created with the ip community-list command.
Copyright © 2010, Juniper Networks, Inc. 76
JunosE 11.2.x BGP and MPLS Configuration Guide