I was making a tour of my roof today and it reminded me to ask a couple of questions.
1- there are two 6" round plastic objects that kinda look like vents, but are not the tank vents. My tank vents are the smaller "normal" looking ones. One of them is right near the back end of the trailer, and the other near midway of the bedroom up front. Centerline of the roof.
2- on the curb side, just above my feet if I was reclining in my chair, are two 1/2" round rods sticking through a bunch of roof caulk. They don't stick up very far above the roof line
Both of those have me stumped, as I haven't seen anything like either on a RV roof

The six inch roof vents are the Attic Vents. Make sure the top section is secure as many RVs with those vents have had the top section come unscrewed and lost on the road. Your other two rods as you call them are the terminators on the coaxial connections if using a roof top mounted satellite dish.

Thanks for the answers! I noticed the tank vents are deteriorating and the attic vents aren't far behind. Just another batch of projects. At least the weather is getting nicer, so the chores aren't so bad to do now. With two rv's to maintain, summer will just about be over when I get caught up, Haha. Bringing the motorhome here tomorrow to dewinterize.