Reference: https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/mp_te_diffserv/configuration/15-mt/mp-te- diffserv-15-mt-book/mp-te-diffserv-aw.html MPLS traffic engineering supports only a single IGP process/instance The MPLS traffic engineering feature does not support routing and signaling of LSPs over unnumbered IP links. Reference: https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/mp_te_path_setup/configuration/xe-3s/mp-te-path-setup-xe-3s-book/mp-te-enhance-xe.html