By default, a non-label route can be iterated to only the outbound interface and next hop and cannot be iterated to the tunnel. After the following command is configured, a non-label route of the public network can inherit the tunnel ID of IGP (or the static route). Thus, MPLS forwarding is implemented.
        The route recursive-lookup tunnel command is used to enable the non-label route of the public network to be iterated to the tunnel and is valid for only non-label routes of the public network that require iteration. To implement precise control, you can specify an optional list of IP address prefixes to filter the non-label routes that need to be iterated to the tunnel. You can run the undo route recursive-lookup tunnel command to restore the default configuration.