Forces the CSPF calculation to include any specified interface when creating an LSP.
The command is disabled, by default.
MPLS policy mode.
The command may be dynamically turned on or off. Turning the command off or on has no effect on LSPs that have already been established (primary and secondary). For LSPs that are currently retried, changing the constraint setting changes the behavior on the next retry such as when an LSP whose path is configured to use that interface fails to come up due to an interface down condition.
The command has significance for the ingress node only, where the CSPF calculation takes place for an LSP or a detour segment.
The no form of the command disables the configuration.
MPLS is supported on the Extreme 8820, SLX 9740, SLX 9640, and SLX 9540 devices only.
The following example configures the command.
device# configure device(config)# router mpls device(config-router-mpls)# policy device(config-router-mpls-policy)# cspf-interface-constraint