What is the duty of a Kshatriya?

In the 31st verse of chapter 2 of Bhagavad Gita for happiness, Lord Krishna tells Arjuna that as a Kshatriya, it is critical that Arjuna think about his primary duty. There is nothing more important to him than fight. According to Krishna, those fight battles for the cause of discipline or dharma — there is no violence in this act. Rather such battles are for a noble cause, and such warriors go to heaven.