Traffic Forwarding - HP MSR2000 Configuration Manual

To avoid flapping caused by improper preemptions, the setup priority value of a tunnel must be
equal to or greater than the holding priority value.
Explicit path
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Explicit path specifies the nodes to pass and the nodes to not pass for a tunnel.
Explicit paths include the following types:
Strict explicit path—Among the nodes that the path must traverse, a node and its previous hop
must be connected directly.
Loose explicit path—Among the nodes that the path must traverse, a node and its previous hop
can be connected indirectly.
Strict explicit path precisely specifies the path that an MPLS TE tunnel must traverse. Loose explicit
path vaguely specifies the path that an MPLS TE tunnel must traverse. Strict explicit path and loose
explicit path can be used together to specify that some nodes are directly connected and some
nodes have other nodes in between.
Setting up a CRLSP through RSVP-TE
After calculating a path by using CSPF, MPLS TE uses a label distribution protocol to set up the CRLSP and
reserves resources on each node of the path.
The device supports the label distribution protocol of RSVP-TE for MPLS TE. Resource Reservation Protocol
(RSVP) reserves resources on each node along a path. Extended RSVP can support MPLS label
distribution and allow resource reservation information to be transmitted with label bindings. This
extended RSVP is called RSVP-TE.
For more information about RSVP, see "Configuring RSVP."

Traffic forwarding

After an MPLS TE tunnel is established, traffic is not forwarded on the tunnel automatically. You must
direct the traffic to the tunnel by using one of the following methods.
Static routing
You can direct traffic to an MPLS TE tunnel by creating a static route that reaches the destination through
the tunnel interface. This is the easiest way to implement MPLS TE tunnel forwarding. When the traffic to
multiple networks is to be forwarded through the MPLS TE tunnel, you must configure multiple static routes,
which are complicated to configure and difficult to maintain.
For more information about static routing, see Layer 3—IP Routing Configuration Guide.
Policy-based routing
You can configure PBR on the ingress interface of traffic to direct the traffic that matches an ACL to the
MPLS TE tunnel interface.
PBR can match the traffic to be forwarded on the tunnel not only by destination IP address, but also by
source IP address, protocol type, and other criteria. Compared with static routing, PBR is more flexible
but requires more complicated configuration.
For more information about policy-based routing, see Layer 3—IP Routing Configuration Guide.
Automatic route advertisement
You can also configure automatic route advertisement to forward traffic through an MPLS TE tunnel.
Automatic route advertisement distributes the MPLS TE tunnel to the IGP (OSPF or IS-IS), so the MPLS TE
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