Use a sub-domain as an entire site with others sub-domains


I try to install a multisite with "multi domains" and "domain mapping plugins".

I want a portal with subdomains and each one must be a full-fledged website. Then, these sub-domains will have other subdomains.

example: the portal is called

there are three sites in the portal:, and and I'll have to create,, etc..

The site site1, site2 and site3 be entities and it must be possible to point to it.

Currently, site1 sites site2 and site3 are aliases for and everything is installed on a shared server to a development phase. Unfortunately, the site is not different between site1 sites site2 and mysite.

Versions are up to date and there are only three plugins (wpmu dev, multi-domains, domain mapping).

My question is ; how to make the subdomain (used in multi- domains) may also be an entire site ?