If an LSR is configured for load balancing and an entropy label is found in the label stack, the LSR will take the entropy label into account in the hashing algorithm as follows:
label-only: the entropy label is used as input to the hash routine and the rest of the label stack is ignored.
label-ip: the entropy label and the IP packet are used as input to the hash routine and the rest of the label stack is ignored.
If penultimate hop popping (PHP) has been requested by a next-hop LER, the LSR will retain any entropy label found immediately below the tunnel label that is to be popped. The system will retain and use the entropy label information as input to the local hash routine if an applicable LSR load-balancing mode has been configured.
For more information on LSR load balancing, see the LSR Hashing section in the 7705 SAR Interface Configuration Guide.