Hi in same web application how to create a new site collection based on existing subsite. I have below subsite:
I want to create a new site collection and import subsite1 under it:
You must export and import existed site to new blank site, if you want to move it to new site collection:
http://webapp/sites/subsite1 -Path "subsite1_export.cmp"
Import-SPWeb http://webapp2/sitecoll/subweb2 -Path subsite1_export.cmp -IncludeUserSecurity -Overwrite