Master port no longer exists as of 6.40. This was due to confusion between master port and bridge, they do the same thing but in different ways in the background.
The new way to do master port is to add interfaces to a bridge. See /interfaces bridge and /interfaces bridge port.
Please about this problem can you confirm the substitute command for this?
/interface ethernet
set 0 name=ether1-gateway
set 1 name=ether2-master-local
set 2 master-port=ether2-master-local name=ether3-slave-local
set 3 master-port=ether2-master-local name=ether4-slave-local
set 4 master-port=ether2-master-local name=ether5-slave-local
I readed is can be solved with a bridge, but I use a script for Movistar provider and I need exist this names.
Regards