I currently have two WordPress installations. One is in the web root directory and is a multisite installation using subdirectories, not subdomains. The other is a test site, in a subdirectory of the web root directory, and is currently a single-site installation. I would like to convert the test site to a multisite installation without disturbing the existing multisite installation.
Since this is a test site meant for checking new or updated plugins and themes before installing on the main network, it can’t share themes or plugins with the existing multisite installation. In other words, I can’t use a multi network.
I’m happy to move the test site to a subdomain if that is needed to allow a second network; however, I don’t want to disturb the main sites if I can avoid it. Is there a way to have two multisite installations on the same server?
Read more here:: How can I create a second multisite network in a subdirectory?