Juniper JUNOSE 11.2.X BGP AND MPLS, Configuration Manual

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host1:pe1(config-route-map)# match mpls-label
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Use the no version to remove the configuration.
•
See match mpls-label.
neighbor send-label
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Use to configure a BGP peer to distribute an MPLS label with the advertisements for
its IPv4 and IPv6 routes.
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This command enables BGP to dynamically negotiate SAFI 1 and SAFI 4 with this
neighbor.
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Example
host1(config-router-af)# neighbor 10.19.1.2 send-label
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Use the no version to halt distribution of the MPLS label with route advertisements.
•
See neighbor send-label.
set mpls-label
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Use to configure BGP to advertise prefixes that match the route map as labeled prefixes.
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Example
host1:pe1(config-route-map)# set mpls-label
•
Use the no version to remove the configuration.
•
See set mpls-label.
BGP Next-Hop-Self
When a BGP router reports itself as the next hop, whether because of an explicit neighbor
next-hop-self configuration or implicitly as a result of participating in an EBGP session,
BGP allocates a new in label and adds an entry to the MPLS forwarding table, creating
a label-to-next-hop mapping.
When a BGP router does not report itself as the next hop, whether because of an explicit
neighbor next-hop-unchanged configuration or implicitly as a result of a participating
in an IBGP session, BGP does not allocate a new in label. Instead, if the route is advertised
as a labeled route, BGP uses the existing out label. This feature is used mainly on route
reflectors.
The determination to allocate an in label is made only after the outbound route map has
been processed. Therefore, the in label allocation and the creation of the
label-to-next-hop mapping are performed after the need is apparent, conserving the
number of in labels allocated.
BGP Processing of Received Routes
BGP processes received routes differently depending on whether the route is labeled or
unlabeled, unicast or VPN.
459 Copyright © 2010, Juniper Networks, Inc.
Chapter 6: Configuring BGP-MPLS Applications