Hi friends,
i have an e-commerce site Suppose (abc) in which i deal for every product. i have made round about 20000 mini sites hosted on same ip or server for every product. i have minimum 10 individual mini sites consisting of 5-6 Pages for a product. Well Question is that : When ever a user click on a product listed in mini sites its directly goes to my main site (abc) , Now i want to ask is it ethical seo, if its not why ? will google ban me and why ?

I think so google may ban your site, cos it does seems to obligate some of the rules of SEO and it comes quite close to the pathway of Black Hat SEO

I do not think that it is ethical seo. Here is one more issue with your strategy. When 50-80% of your backlinks came from a single IP, this will make you more problematic.