MPLS and RSVP
7450 ESS MPLS Guide Page 105
metric which is used by default. Note that the TE metric is only used in CSPF computations for
MPLS paths and not in the regular SPF computation for IP reachability.
Admin Group Support on Facility Bypass Backup LSP
This feature provides for the inclusion of the LSP primary path admin-group constraints in the
computation of a Fast ReRoute (FRR) facility bypass backup LSP to protect the primary LSP path
by all nodes in the LSP path.
This feature is supported with the following LSP types and in both intra-area and inter-area TE
where applicable:
• Primary path of a RSVP P2P LSP.
• S2L path of an RSVP P2MP LSP instance
• LSP template for an S2L path of an RSVP P2MP LSP instance.
• LSP template for auto-created RSVP P2P LSP in intra-area TE.
Procedures at Head-End Node
The user enables the signaling of the primary LSP path admin-group constraints in the FRR object
at the ingress LER with the following CLI command:
configure>router>mpls>lsp>fast-reroute>propagate-admin-group
When this command is enabled at the ingress LER, the admin-group constraints configured in the
context of the P2P LSP primary path, or the ones configured in the context of the LSP and
inherited by the primary path, are copied into the FAST_REROUTE object. The admin-group
constraints are copied into the include-any or exclude-any fields.
The ingress LER thus propagates these constraints to the downstream nodes during the signaling
of the LSP to allow them to include the admin-group constraints in the selection of the FRR
backup LSP for protecting the LSP primary path.
The ingress LER will insert the FAST_REROUTE object by default in a primary LSP path
message. If the user disables the object using the following command, the admin-group constraints
will not be propagated: configure>router>mpls>no frr-object.
Note that the same admin-group constraints can be copied into the Session Attribute object. They
are intended for the use of an LSR, typically an ABR, to expand the ERO of an inter-area LSP
path. They are also used by any LSR node in the path of a CSPF or non-CSPF LSP to check the
admin-group constraints against the ERO regardless if the hop is strict or loose. These are
governed strictly by the command:
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