Do you have an outside GFCI outlet? Could be the inside outlets are daisy chained from an outside GFCI outlet.
Check all your circuit breakers. A tripped breaker is not visually obvious. It does not flip to the OFF position when tripped, just moves a little off of the ON position. Press on the breaker handles and if one feels "soft" then it is probably tripped. Turn it off and back on to reset it.
If you have a 50 amp trailer, then it could be that the 50 amp service is missing one hot leg. If you are comfortable checking electricity, then you could pull the cover from the breaker panel and see if the main 50 amp breaker has power to both hot legs.