I think there is no vaishya caste in tamilnadu."
Chettiars are Vaisyas.
Nadars are self declared Vaisyas.
Khatri in Punjab are Scythian origin. they are not khastriyas. 75 to 80 percent of Punjab poupulaiton are Scythian in origin. they are non Vedic. they are considered shudras by Brahmins. there is one more Scythian in south that is nairs in kerala and bunts. the nairs were bought from north to serve Brahmins by kadambas kannada king. Scythian have adopted traditions from which ever group they have come across those time. as far as tamil nadu is concerned they are total shudras and one precent Brahmins rule in that state. just like Punjab(outside origin) tamilians are classified as afro race(outside origin) in india. they have nonthing to do with telegus and kannada people in common.
Kannadigas are classified as indeginous which is native to the land. the last number of khastriyas are in kannada caste. the idigas are classified as somavamshi khastriyas, the kurubas (yadav or Chandra vamshi khastriyas) vokkaligas or gowdas as kurumi khastriyas same has north part of india, the special one in this gangitikar gowdas in mandya and in mysore region are surya vamshi and ganga kula khastriyas(ganga dynasty, chalukyas all are surya vamshi. the Karnataka dyanasty are chutu(pallavas branch of it), rastrakutas, solanki, chalukyas, pallavas, alupas(idigas) same pandyas, kadambas.
one more kannadigas and telegu people are not dravidians. the tamils, malyalis, Bengalis even kashmiris have been classified under proto Dravidian family. it it high time to wake up for telegu people. Learn from kannadigas how they differeniate themselves unique in there traditions, culture, customs compared to other south indian. the kannadigas hate tamils as usual, kannadigas from the beginning consider tamils are untouchable. Brahmins have classified nadars has shudras(there women was not suppose to cover there breast durning those times, same has nairs in kerala, both are considered shudras by Brahmins. in t. tamil nadu even the khastriyas and vaishya in varna is missing from the beginning even Brahmins in that state saying the same.
where ever british ruled the in india and made there centre providence all that region had only had shudras and Brahmins in common, tamils, Bengalis, Punjab and even the so called gujuratis(15 percent vaishyas mixed with shudras).