This is the one of the first ritual that happens. The priest along with both the families determine
What is Gotra?
The term gotra means clan. It refers to people who are descendants in an unbroken male line from a common male ancestor. All members of a particular gotra are believed to possess certain common characteristics by way of nature or profession.
Same Gotra Marriages
Marriages within the gotra are not permitted under the rule of exogamy (social arrangement where marriage is allowed only outside of a social group) in the traditional matrimonial system. People within the gotra are regarded as kins.
An acceptable social workaround for same gotra marriages is to perform a Dathu (adoption) of the bride to a family of different gotra (usually dathu is given to the bride's maternal uncle who obviously belongs to different gotra by the same rule) and let them perform the kanyadaan.
Difference between Kul and Gotra
A kula is a set of people following similar cultural rituals, often worshiping the same divinity (the Kula-Devata, god of the clan). Kula does not relate to lineage or caste like gotra. In fact, it is possible to change one's kula, based on one's faith.