Miniumum total ordering quantity

I’m trying to set a minimum number of total ordering quantity, so like a visitor have to checkout with at least X number of products in their cart, otherwise they cannot order. I can only see how to set a minimum number of quantity per product, not set the limit on the cart. Am I missing something? If not, how can I achieve this? Thanks!

Summing of quanities in the cart to a minimum number is not supported in the standard cart. You would be looking at a custom modification.