I am going to arrival in Vietnam at the Phu My Port (cruise from Singapore). Can I have my visa application processed online and get visa upon my arrival?
Be kindly advised that you cannot apply for a visa on arrival since it is applicable to those who travel to Vietnam by air only. You, in your case, should contact the most convenient Vietnam Embassy to apply for a visa. You also can contact Cruise company to ask whether they might assist you with visa for visiting Vietnam.
Wish you a safe and nice trip.