JET: Programming FTIs

You can use the Interfaces Service API to configure flexible tunnel interfaces (FTIs) in Junos OS. You can change the attributes of the tunnel configurations for the unit under an existing FTI but cannot change the existing tunnel encapsulation type using the APIs. For the following families, you can configure only the listed attributes when you use JET APIs: 

•  inet and inet6: address and destination-udp-port 
•  mpls and iso: destination-udp-port