When ECMP is enabled and multiple equal-cost next-hops exist for the IGP route, the ingress IOM or line card sprays the packets for this route based on the hashing routine currently supported for IPv4 packets.
When the preferred RTM entry corresponds to an LDP shortcut route, spraying is performed across the multiple next-hops for the LDP FEC. The FEC next-hops can either be direct link LDP neighbors or T-LDP neighbors reachable over RSVP LSPs, in the case of LDP-over-RSVP, but not both. This is as per ECMP for LDP.
When the preferred RTM entry corresponds to a regular IP route, spraying is performed across regular IP next-hops for the prefix.
Spraying across regular IP next-hops and LDP-shortcut next-hops concurrently is not supported.