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

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When the MPLS tunnel (RSVP-TE or LDP) to the next hop of the best route goes down,
the VPNv4 route reflector immediately advertises the next-best route (if any) without
waiting for the MP-IBGP session to go down. In this example, that route is through PE 2.
check-vpn-next-hops
•
Use to enable a BGP speaker to consider the reachability of the next hop when the
speaker determines which VPNv4 or VPNv6 route is the best path to a prefix.
•
Verifying the reachability of the next hop is disabled by default.
•
This command is available only in the context of the VPNv4 unicast and VPNv6 unicast
address families. The behavior is the same for both address families.
•
Use the show ip bgp vpnv4 all summary or show bgp ipv6 vpnv6 all summary
command to view the status of next hop reachability checking.
•
This command takes effect immediately.
•
Example
host1:pe1(config-router-af)# check-vpn-next-hops
•
Use the no version to halt the verification of next-hop reachability by the BGP speaker.
•
See check-vpn-next-hops.
Configuring BGP to Send Labeled and Unlabeled Unicast Routes
You can issue the neighbor send-label command to enable BGP to exchange both
labeled and unlabeled unicast routes in the same address family (same AFI) over the
same BGP peering session. The routes can be IPv4 or IPv6 routes. When you issue the
neighbor send-label command, JunosE always proposes SAFI 4 and SAFI 1. If this
command has not been configured, then JunosE proposes only SAFI 1.
A route is advertised as a labeled route within a given BGP peering session in either of
the following cases:
• You issue the neighbor send-label command, but no outbound route map has been
configured.
•
You issue the neighbor send-label command and an outbound route map has been
configured, and the route map executes a set mpls-label clause for the advertised
route.
In all other cases, the route is advertised as an unlabeled route.
match mpls-label
•
Use to match on MPLS-labeled routes by including as a clause in a route map. The
clause matches the route only if the route has a label.
•
By including this command in the appropriate route map (export, global export, global
import route map), you can restrict importing or exporting to only labeled or only
unlabeled routes.
•
Example
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JunosE 11.2.x BGP and MPLS Configuration Guide