Something is causing the server to crash. I dont know exactly what it is but I have a couple of ideas. I am getting more RAM for the server since this is the most obvious solution and if that does not fix the problem then I will have to start going through the plugins starting with the voting rewards.
The question now is if we should keep starting the server and letting it crash. This can be dangerous to the server files and can corrupt a world file quickly. I am going to keep the server down for the moment but may put it online for short periods. I expect to have the upgraded RAM by tomorrow when I get off work so things will hopefully be better by then. I will keep you posted as the situation changes.