Express segments using SR-TE underlay

We've introduced SR-TE underlay path support for express segments to enable end-to-end transport of segment routing-traffic engineered (SR-TE) label-switched paths (LSPs) for very large multi-domain networks. The path is automated using segment-set or template policies for uncolored or colored segment routing policies. The rib-group configuration is required to import addresses to inet.3 for colored segment routing policies. When the express segments underlay is colored SR-TE, you need to configure the no-chained-composite-next-hop statement at the [edit protocols sourcepacket- routing] hierarchy level for the express segment to install the correct flattened next hop. 

This feature has the following limitations: 

•  When the express segments underlay is colored SR-TE, the express segment does not inherit the SR-TE LSP underlay attributes (SR-TE name, metric). 
•  The install-nexthop option at the [edit policy-options policy-statement policy-name term termname then] hierarchy level to filter a specific SR-TE LSP bu its name is not supported. 
•  Express segments do not consider the respective weights of the primary and secondary segment lists of SR-TE LSP. Secondary LSP segments can be preferred for traffic even when the primary segment is up.